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The Effect of Hormonal Modification on Prostatic Morphology
THE EFFECT OF HOR\IONAL TvIODIFICATION 0~ PROSTATIC MOHPHULOG :.IAHVIN W. WOODRUFF
AND
CARLOS PEREZlVlESA
Frnm. lhe Departmcn/8 of C'i'Olor,y ancl Patholouy, Ro.swell Park Jfemorial Institute, B11ff"1ilo, Y V.
In animals, ::is well as man,
observed that estrogen ,:;aused a diminution in volume of prostntic secretion in the clog uncl further demonstrated that this effect could be blocked by injection with testosterone propionate. A sim.ibr antagonistic effect of Pstrogen-androgcn combination therapy on the growth of the prostate glands in intac:t rats was reported by Woodruff and Umiker in 19(50. These latter studies re,,cakcl that when the administered androgen fraction \Yas increased, prostatic weight increased and histological evidc:nce of glandular hypertrophy developccl. , when the estrogenie fraction was increasrd, prostatic weight decreased and prostatie atrophy ensued. HmY·" ever, when estrogen: androgen was administered in a ratio of 2. l, no elrnnge in prostatic mmphology was noted. Although these inYe~tigatini ende::ivorn would tcncl to indicate a direct antagonistic: effect of estrogen and androgen on the growth and furwtion of the prostate gland, these previous obserrn.tions were noted in animals with intact anclrcnal and pituitary glands, In order to determine if this adually n·presented a direct effect of estrogen and androgen on the tJrostate gland or rather mw which was mcclintccl through other endocrine organ systems this serit>s of experiments in hormonally moclificcl animals was undertaken. The effect of estrogen and androgen, alone, and in combination, npon the growth ::ind histology of the intact rat's prostate gland was used as the control mocld for the succeeding e:--:periAccepted for publication December 5, 1961. Read at annual meeting of :\orth Central Section, American Urological Association, Inc., Cin-
cinnati, Ohio, September 27-<,0, Hl6I.
mcnts. These intad animal results \\Tl'l' then elm1pared with observations carried out in cmimals following hypoph:rncctomy, arlre11al('('t01n.l or castration. J. Ejfcct of cstrnr1en and anrlroyen on the prnstu.t-ic weiyht of intact 11ni111.als
TAB LB
'
Number Group I oI An_ i- ES t romals gen
Androgen
A Ye rage Body \\'eight
'
i -i----
A
10
B
8 10
C
D E
l1 10
micro-
micro-
grams
r;rams
250 250 )25
125 250 ,500
grams
261 .5 275 0 2DG 4 330.:3 32G . G
milli-
:30 \l
014
271. :3 :l:34.0 4\)5. 4 :t>t 4
. 0\)8 .11:1
i
u,o
. Oll!l
:IJETHOD
Two hundred uncl thirty-tlm'e matitn' nm.Jc albino rats of tlw Spragmi-Dawley ~train :1,·pr;i,g ing 28,5 gm. in body weight were used. TlH'cJ('. animals were thc:n grouped into fom l) proRtatic response to androgen ancl estrogen in intact animals, 2) prostatie response to and estrogen in hypophysectomized prnstatic response to androgen and ( strogen 1n aclrenaleetomized animals and 4) sponse to androgen and estrogen n1 animals. The mern bers of eaeh incli \·iclual were divided into 5 groups and receiYe<.l a senc,. of seven intramuscnlar injections of estrad101 n1Jerate, testoskronc propio11ak, alone, or in combination on alternate O\ rr a 2-\\ <'i'l, period. Tlw hormonal prri.mrations were ministered in the following qmwtities: Group i\.: 2,50 microgran1~ of e~trogen Group B: 250 micrograms of e~trog:(;11 :incl L:2:') rnierograms of androgen Group C: 125 microgram~ of estrogen and 2,51) micrograms of anclrog('l1 Group D: 500 rnicrogranrn of :u1clroge11 Group E: l:ntrc,ated controlc On the fourteenth e:--:iwriment , the n.nimnb 0
274
M. W. WOODRUFF AND C. PEREZ-MESA
FIG. 1. Changes in prostatic histology with estrogen and androgen administration to intact animals. A, normal histology of rat prostate gland (untreated control). B, prostate gland after estrogen: androgen in 2: 1 ratio with maintenance of normal appearance. C, prostate gland following administration of 250 micrograms of estrogen (group A). Xote dilatation of acini and conversion of tall columnar epithelium to low cuboidal in type. D, prostate gland following 250 micrograms of androgen (group D). Note accentuation of glandular folds and increase in size of epithelial cells.
were sacrificed by ether suffocation and the ventral lobes of the prostate glands were excised and weighed on a Roller-Smith torsion balance. The prostatic tissue was then fixed in buffered forma-
lin for 48 hours. Paraffin sections of each organ were stained with hemotoxylin and eosin. fn addition, representative sections of prostatic tissue were studied using the following tech-
PR08TATIC MORPHOLOGY
TABI,E
2. Effect of estror1en and cmdrouen on the proslatic weight of hypophysectondzed animals -
Group ------
A
B C D,*
D,t F~, *
E,t
i I
1\umber of Animals i
I
I
14 12 13
I
Estrogen
Androgen
I
'"' i~"""
micrograrns
!
125
(i
8 8 9
-·--------
125 250 500 500
Hypophysectomized controls Hypophysectomized controls
I l'_rostatic
\Yeighl Body Weight I -~---~ per cent
Average Body Weight
Average Prostatic Weignt
grams
rnilLigrams
211.4 213.2 225.4 23G.O 247.5 202.5 224.clc
lO(i
.050
225.8 373.7 +25.8 429.8 15
. JOG .166 .180
l(j
.174 .007 .007
* Autopsied 2 weeks following hypophysectomy. j- Autopsied 4 weeks following hypophysectomy.
niques: 1) l\Iasson's tric:hrome and l\fallory trichromP stains for e,·aluation of stromal alkration, 2) Bismarck brmYn stain for mast cell presence, and 3) Schiff rm('tion for changes in mnrnpolysaceharides. HE8ULTS
Prostatic response to androgen and estrogen in intart animals. Prostatic changC's in ,Ycight and histolog)· for the control group of intact animals following administration of androgen and estrogen alone and in combination are noted in table 1. Auimab treated with estrogen alone showed a marked decrease in prostatic ,wight, while thos,' that reeoiYecl only androgt:n displayed a small increase in prostatic weight. ,nwn estrogen ancl androgen ,wrr aclrninisterecl in a ratio of 2: 1 (group B), no significant change in prostatic ,wight was noted as c:omparocl to tho uninjeckd control group E. Biological titration was obsen-ccl wlwn this 2: 1 ratio was changed, the weight of the prostate glands decrPasing ,Yith increasrd increments of ('Strogen. Conn~rnely, prostatic weight increasl'd at higher amlrogrn: estrogen ratios. Histologically, estrogen causrd a dilatation of the prostatic acini and COlffPrsion of the normal tall columnar epithelium to ]my cnboidal in type. There is almost complrte disappcarnncr of cytoplasrnic Yacuolcs and the' nuclei appear smal!Pr in siz<; (fig. 1, C). Spec:ial staining techniques revealed an apparent increase in mast cell number. 1n those animals administered estrogen and at1(lrog('l1 in exactly 2:1 ratio (fig. 1, B), no histologic changes ,wre noted and tissue sections from
these animals were microscopically indistinguishable from those of the untreated controls 1, .-1). l\Iany cf the rats whi('h n'ceiwd androgen alone, or estrogen: androgen combination of 1 : 2 exhibited eviclrnce of prostatic stimulation Pxpre:c;sed by the increa:c;e in size of epithilial cellr;, accentuation of glandular folds and tlw appear ance of cytoplasn1ic rnrnoles (fig. l, D). Prostatic response to androgen and estrogen in hypophysectomized animals. ln order to nvoid. pro static atrophy following hypophysectomy, tlw animals wen' initially maintained on 500 micrograms of testosterone propionate enT)' other for a period of 2 weeks prior to bl'ing placed on the 14 day closagC' scheduk of estrogen and androgen similar to the format of the 1nwediug: experiment. The weight changes of the prostate glands of the hypophysectomized animals are recorded in table 2. The smallest prcstate glands of the entir(' series of experiments were noted in the uninjectrd hypophysectomized control~ in groups E1 and E2. Prostatic weight was (i per cent of norma 1 with glands anraging 15 mg. obtained. Estrogen administration to the hypophysectomized animals caused a decrease in prostatir: weight but not to the same degree as hypoph) sectomy alone. Those animals treated with estrogen:anclrogen in ratio of 1 :2 (group C) and androgen alone (group D) displa.n'd marked prostatic weight gain. ·when estrogen: androgen were administered in a ratio of 2:1 (group 13), the prostatic weights re mained normal and WC'l't' comparable in size t(l those of intact uninjectecl control animals.
a,
276
M. W. WOODRUFF AND C. PEREZ-MESA
FIG. 2. Changes in prostatic histology with estrogen and androgen administration to hypophysectomized animals. A, appearance of prostate gland 2 weeks following hypophysectomy. Note marked atrophy, lining cells are low, acini small with an apparent increase in interacinar tissue. B, prostate following hypophysectomy and estrogen:androgen administration of 2:1 showing normal histologic appearance. C, prostate following hypophysectomy and estrogen showing dilatation of acini and conversion of tall columnar epithelium to low cuboidal in type. D, prostate of hypophysectomized animal treated with androgen. Note prostatic hyperplasia.
277
PROSTATIC MORPHOLOGY TABLE
3. Effect of estrogen and androgen on the prostatic weight of adrenalectomized animals
Group
Number of Animals
A
9 11
B C D E
10
11 10
Estrogen
Androgen
1nicrogranis
niicrograms
250 250 125 -
-
125 250 500
Adrenalectomized controls
Average Body Weight
Average Prostatic Weight
Prostatic Weight Body Weight
grants
milligrams
per cent
285.0 290.1 303.7 336.7 335.9
127.3 308.9 348.3 532.2 347.3
.045 .106 .115 .158 .103
I
Risto logically, the uninjected hypophysectomized animals (fig. 2, A) show a marked decrease in size of the individual acini. The lining cells are low cuboidal in type with closely packed nuclei making the cytoplasm barely visible. The interacinar tissue and the mast cells appear more prominent; however, further quantitative studies are necessary to determine the magnitude of these changes. These glands resemble the appearance of immature prostatic tissue. In those animals receiving estrogen: androgen in ratio of 2: 1 (fig. 2, B), the prostate glands appeared histologically normal. The acini were lined with tall columnar cells and in general appeared similar to those seen in the uninjected control animals (fig. 1, B). Hypophysectomized animals treated with estrogen following 2 weeks of supportive androgenic therapy displayed signs of atrophy as measured by dilated glands and lowering of the lining cells of the acini (fig. 2, C). Those animals injected with androgen alone showed marked prostatic stimulation as evidenced by increased glandular infolding, hyperplasia and increased mitosis (fig. 2, D). Prostatic response to androgen and estrogen in adrenalectomized animals. In this experiment, the animals were subjected to bilateral adrenalectomy and on the day following surgery started on the estrogen: androgen therapy for 2 weeks. Prostatic weight changes of the adrenalectomized animals following hormonal therapy are noted in table 3. Adrenalectomy alone without hormonal supplement had no effect on prosta tic weight (group E). Androgen administration caused an increase and estrogen a decrease of prostatic weight. Again noted was maintenance of normal size glands when estrogen and androgen were administered in ratio of 2: 1 in the absence of the adrenal glands.
Histologically, the untreated adrenalectomized control animals maintained normal microscopic appearance (fig. 3, A). Estrogen alone caused marked atrophy with dilatation of the glands and flattening of the epithelium (fig. 3, B). When the estrogen:androgen ratio was 1 :2 or greater, the prostate glands displayed evidence of hyperplasia including pseudostratification and vacuolization (fig. 3, C). Figure 3, D shows the histologic appearance of the prostate glands following administration of estrogen : androgen in 2 : 1 ratio following adrenalectomy. Again the prostate appearance is normal and microscopically indistinguishable from that of the uninjected intact control animal. Prostatic response of androgen and estrogen in castrated animals. The animals in this experiment had bilateral orchiectomy on the day prior to the initiation of their 2 week course of androgen and estrogen. The weight changes of the prostate gland are noted in table 4. Orchiectomized control animals receiving no supportive hormonal therapy (group E) showed a marked diminution in prostatic weight while those castrated animals that were maintained on androgen (group D) showed a moderate increase. When estrogen : androgen was administered in 2: 1 ratio, prostatic weight approached the lower limits of normal. Histologically, orchiectomy alone and in combination with estrogen was observed to cause marked atrophy, flattening of the lining epithelium with increased prominence of the mast cells and interglandular stroma (fig. 4, A and B). Castration and androgen (fig. 4, C) resulted in focal areas of hyperplasia. The prostates of those animals receiving estrogen: androgen in ratio of 2: 1 and 1 : 2 microscopically appeared normal with no evidence of atrophy or hypertrophy noted (fig. 4, D).
278
M. W. WOODRUFF AND C. PEREZ-MESA
Fm. 3. Changes in rat prostate histology with estrogen and androgen administration following bilateral adrenalectomy. A, rat prostate following adrenalectomy. Note normal histologic appearance. B, adrenalectomized rat prostate following estrogen, showing marked atrophy and flattening of acinar epithelium. C, androgen and adrenalectomy. Note evidence of hyperplasia. D, adrenalectomized animals receiving estrogen:androgen in 2:1 ratio. Note normal histologic appearance. DISCUSSION
This group of experiments supports the concept that estrogens produce atrophy and androgens hypertrophy of the prostate glands in both intact rats and in those previously hormonaly
modified by hypophysectomy, adrenalectomy and castration. The atrophy induced by estrogen, hypophysectomy and castration may be inhibited by the administration of androgen. Dy utilization of the rat prostate gland as a
PROSTATIC MORPHOLOGY
279
Frn. 4. Changes in rat prostate histology with estrogen and androgen following castration. A, prostate following orchiectomy showing marked atrophy. Note flattening of lining epithelium and increased prominence of interglandular stroma. B, rat prostate following combined orchiectomy and estrogen showing extreme atrophy similar to that noted with orchiectomy alone. C, prostate of animal receiving androgen following orchiectomy showing areas of hyperplasia. D, orchiectomized animal treated with estrogen: androgen in ra.tio of 2: 1. Note maintenance of normal prostatic histology.
280
M. W. WOODRUFF AND C. PEREZ-MESA
TABLE 4. Effect of estrogen and androgen on the prostatic weight of orchiectomized animals Group
Number of Animals
A B C D E
11
14 10
13 15
Estrogen
Androgen
micrograms
micrograms
250 250 125
-
125 250 500 Orchiectomized controls
modality for biological titration, it was demonstrated that when estrogen: androgen were administered in ratio of 2: 1, the prostate gland was of normal weight and histology, even in the absence of the pituitary, adrenals or testes. This would indicate that the action of exogenous estrogen and androgen is a direct one on prostatic morphology, one which continues to be effective after the endogenous source of estrogen and androgen stimulation and production is ablated. The greatest degree of prostatic atrophy was obtained by hypophysectomy alone and demonstrates the important role of the pituitary gland in prostatic growth stimulation. Although the results obtained from animal experimentation are not necessarily applicable to man, these experiments would suggest that the greatest degree of prostatic growth inhibition can be obtained by hypophysectomy alone. Adrenalectomy alone effected no change in normal prostatic morphology. When adrenalectomy was combined with estrogen, prostatic atrophy ensued but not to the extreme degree noted by hypophysectomy. Orchiectomy induced about the same degree of prostatic atrophy as estrogen. When orchiectomy and estrogen were combined in the same animal, the changes in prostatic weight and histology over a 2 week period were not different than estrogen administration or castration alone. SUMMARY In four separate experiments, estrogen and androgen, alone and in combination, were administered to intact, hypophysectomized, adrenalectomized and castrated animals. The results tend to indicate that there is a direct independent antagonistic effect of exogenous estrogen and androgen on the growth and histology of the prostate gland. Normal prostatic morphology can be main-
Average Body Weight
Average Prostatic Weight
Prostatic Weight Body Weight
grams
milligrams
per cent
283.6 336.3 293.5 378.6 362.3
56.4 296.4 339.2 490.1 50.6
.019 .088 .116 .129 .014
tained following removal of these glands by the administration of estrogen and androgen in a ratio of 2: 1. Hypophysectomy alone effected the greatest degree of prostatic atrophy of all methods tested. REFERENCES FERGUSSON, J. D. AND PAGEL, W.: Some observations on carcinoma of the prostate treated with estrogens as demonstrated by serial biopsies. Brit. J. Surg., 33: 122, 1945. GRAYHACK, J. T., BUNCE, P. L., KEARNS, J. w. AND ScoTT, W.W.: Influence of the pituitary on prostatic response to androgen in the rat. Bull. Johns Hopkins Hosp., 96: 154, 1955. HUGGINS, C. AND CLARK, P. J.: Quantitative studies of prostatic secretion. J. Exper. Med., 72: 747, 1940. HUGGINS, C. AND RussELL, P. S.: Quantitative effects of hypophysectomy on testis and prostate of dogs. Endocrinol., 39: 1, 1946. DE JoNGH, s. E., KoK, D. J. AND VAN DER WOERD, L. A.: Paradoxe Wirkungen des Follikelhormons bei mannlichen Tieren. Arch. Internat. Pharmacodyn. et Ther., 58: 310, 1938. KoRENCHEVSKY, V. AND DENNISON, M.: Histological changes in the organs of rats injected with estrone alone or simultaneously with estrone and testicular hormone. J. Path. & Bact., 41: 323, 1935. MOORE, C.R., PRICE, D. AND GALLAGHER, T. F.: Rat-prostate cytology as testis-hormone indicator and prevention of castration changes by testis-extract injection. Am. J. Anat., 45: 71, 1930. NICOL, T., HELMY, I. D. AND ABOU-ZIKRY, A.: Histological explanation for the beneficial action of endocrine therapy in carcinoma of the prostate. Brit. J. Surg., 40: 166, 1952. PRICE, D.: Normal development of the prostate and seminal vesicles of the rat with study of experimental postnatal modifications. Am. J. Anat., 60: 79, 1936. SCOTT, w. w., HOPKINS, w. J., LUCAS, w. M. AND TESAR, C.: A search for inhibitors of prostatic growth stimulators. J. Urol., 77: 652, 1957. SELYE, H. AND ALBERT, S.: Effect of various steroids in intact male rats. Am. J. Med. Sc., 204: 876, 1942. WooDRUFF, M. W. AND UMIKER, W. 0.: The effect of estrogen and androgen on the rat prostate gland and testes. J. Urol., 84: 162, 1960. ZUCKERMAN, S. AND PARKES, A. S.: Effects of oestrone on prostate and uterus masculinus of various species of Primate. J. Anat., 70: 323, 1936.
AND
CARLOS PEREZlVlESA
Frnm. lhe Departmcn/8 of C'i'Olor,y ancl Patholouy, Ro.swell Park Jfemorial Institute, B11ff"1ilo, Y V.
In animals, ::is well as man,
observed that estrogen ,:;aused a diminution in volume of prostntic secretion in the clog uncl further demonstrated that this effect could be blocked by injection with testosterone propionate. A sim.ibr antagonistic effect of Pstrogen-androgcn combination therapy on the growth of the prostate glands in intac:t rats was reported by Woodruff and Umiker in 19(50. These latter studies re,,cakcl that when the administered androgen fraction \Yas increased, prostatic weight increased and histological evidc:nce of glandular hypertrophy developccl. , when the estrogenie fraction was increasrd, prostatic weight decreased and prostatie atrophy ensued. HmY·" ever, when estrogen: androgen was administered in a ratio of 2. l, no elrnnge in prostatic mmphology was noted. Although these inYe~tigatini ende::ivorn would tcncl to indicate a direct antagonistic: effect of estrogen and androgen on the growth and furwtion of the prostate gland, these previous obserrn.tions were noted in animals with intact anclrcnal and pituitary glands, In order to determine if this adually n·presented a direct effect of estrogen and androgen on the tJrostate gland or rather mw which was mcclintccl through other endocrine organ systems this serit>s of experiments in hormonally moclificcl animals was undertaken. The effect of estrogen and androgen, alone, and in combination, npon the growth ::ind histology of the intact rat's prostate gland was used as the control mocld for the succeeding e:--:periAccepted for publication December 5, 1961. Read at annual meeting of :\orth Central Section, American Urological Association, Inc., Cin-
cinnati, Ohio, September 27-<,0, Hl6I.
mcnts. These intad animal results \\Tl'l' then elm1pared with observations carried out in cmimals following hypoph:rncctomy, arlre11al('('t01n.l or castration. J. Ejfcct of cstrnr1en and anrlroyen on the prnstu.t-ic weiyht of intact 11ni111.als
TAB LB
'
Number Group I oI An_ i- ES t romals gen
Androgen
A Ye rage Body \\'eight
'
i -i----
A
10
B
8 10
C
D E
l1 10
micro-
micro-
grams
r;rams
250 250 )25
125 250 ,500
grams
261 .5 275 0 2DG 4 330.:3 32G . G
milli-
:30 \l
014
271. :3 :l:34.0 4\)5. 4 :t>t 4
. 0\)8 .11:1
i
u,o
. Oll!l
:IJETHOD
Two hundred uncl thirty-tlm'e matitn' nm.Jc albino rats of tlw Spragmi-Dawley ~train :1,·pr;i,g ing 28,5 gm. in body weight were used. TlH'cJ('. animals were thc:n grouped into fom l) proRtatic response to androgen ancl estrogen in intact animals, 2) prostatie response to and estrogen in hypophysectomized prnstatic response to androgen and ( strogen 1n aclrenaleetomized animals and 4) sponse to androgen and estrogen n1 animals. The mern bers of eaeh incli \·iclual were divided into 5 groups and receiYe<.l a senc,. of seven intramuscnlar injections of estrad101 n1Jerate, testoskronc propio11ak, alone, or in combination on alternate O\ rr a 2-\\ <'i'l, period. Tlw hormonal prri.mrations were ministered in the following qmwtities: Group i\.: 2,50 microgran1~ of e~trogen Group B: 250 micrograms of e~trog:(;11 :incl L:2:') rnierograms of androgen Group C: 125 microgram~ of estrogen and 2,51) micrograms of anclrog('l1 Group D: 500 rnicrogranrn of :u1clroge11 Group E: l:ntrc,ated controlc On the fourteenth e:--:iwriment , the n.nimnb 0
274
M. W. WOODRUFF AND C. PEREZ-MESA
FIG. 1. Changes in prostatic histology with estrogen and androgen administration to intact animals. A, normal histology of rat prostate gland (untreated control). B, prostate gland after estrogen: androgen in 2: 1 ratio with maintenance of normal appearance. C, prostate gland following administration of 250 micrograms of estrogen (group A). Xote dilatation of acini and conversion of tall columnar epithelium to low cuboidal in type. D, prostate gland following 250 micrograms of androgen (group D). Note accentuation of glandular folds and increase in size of epithelial cells.
were sacrificed by ether suffocation and the ventral lobes of the prostate glands were excised and weighed on a Roller-Smith torsion balance. The prostatic tissue was then fixed in buffered forma-
lin for 48 hours. Paraffin sections of each organ were stained with hemotoxylin and eosin. fn addition, representative sections of prostatic tissue were studied using the following tech-
PR08TATIC MORPHOLOGY
TABI,E
2. Effect of estror1en and cmdrouen on the proslatic weight of hypophysectondzed animals -
Group ------
A
B C D,*
D,t F~, *
E,t
i I
1\umber of Animals i
I
I
14 12 13
I
Estrogen
Androgen
I
'"' i~"""
micrograrns
!
125
(i
8 8 9
-·--------
125 250 500 500
Hypophysectomized controls Hypophysectomized controls
I l'_rostatic
\Yeighl Body Weight I -~---~ per cent
Average Body Weight
Average Prostatic Weignt
grams
rnilLigrams
211.4 213.2 225.4 23G.O 247.5 202.5 224.clc
lO(i
.050
225.8 373.7 +25.8 429.8 15
. JOG .166 .180
l(j
.174 .007 .007
* Autopsied 2 weeks following hypophysectomy. j- Autopsied 4 weeks following hypophysectomy.
niques: 1) l\Iasson's tric:hrome and l\fallory trichromP stains for e,·aluation of stromal alkration, 2) Bismarck brmYn stain for mast cell presence, and 3) Schiff rm('tion for changes in mnrnpolysaceharides. HE8ULTS
Prostatic response to androgen and estrogen in intart animals. Prostatic changC's in ,Ycight and histolog)· for the control group of intact animals following administration of androgen and estrogen alone and in combination are noted in table 1. Auimab treated with estrogen alone showed a marked decrease in prostatic ,wight, while thos,' that reeoiYecl only androgt:n displayed a small increase in prostatic weight. ,nwn estrogen ancl androgen ,wrr aclrninisterecl in a ratio of 2: 1 (group B), no significant change in prostatic ,wight was noted as c:omparocl to tho uninjeckd control group E. Biological titration was obsen-ccl wlwn this 2: 1 ratio was changed, the weight of the prostate glands decrPasing ,Yith increasrd increments of ('Strogen. Conn~rnely, prostatic weight increasl'd at higher amlrogrn: estrogen ratios. Histologically, estrogen causrd a dilatation of the prostatic acini and COlffPrsion of the normal tall columnar epithelium to ]my cnboidal in type. There is almost complrte disappcarnncr of cytoplasrnic Yacuolcs and the' nuclei appear smal!Pr in siz<; (fig. 1, C). Spec:ial staining techniques revealed an apparent increase in mast cell number. 1n those animals administered estrogen and at1(lrog('l1 in exactly 2:1 ratio (fig. 1, B), no histologic changes ,wre noted and tissue sections from
these animals were microscopically indistinguishable from those of the untreated controls 1, .-1). l\Iany cf the rats whi('h n'ceiwd androgen alone, or estrogen: androgen combination of 1 : 2 exhibited eviclrnce of prostatic stimulation Pxpre:c;sed by the increa:c;e in size of epithilial cellr;, accentuation of glandular folds and tlw appear ance of cytoplasn1ic rnrnoles (fig. l, D). Prostatic response to androgen and estrogen in hypophysectomized animals. ln order to nvoid. pro static atrophy following hypophysectomy, tlw animals wen' initially maintained on 500 micrograms of testosterone propionate enT)' other for a period of 2 weeks prior to bl'ing placed on the 14 day closagC' scheduk of estrogen and androgen similar to the format of the 1nwediug: experiment. The weight changes of the prostate glands of the hypophysectomized animals are recorded in table 2. The smallest prcstate glands of the entir(' series of experiments were noted in the uninjectrd hypophysectomized control~ in groups E1 and E2. Prostatic weight was (i per cent of norma 1 with glands anraging 15 mg. obtained. Estrogen administration to the hypophysectomized animals caused a decrease in prostatir: weight but not to the same degree as hypoph) sectomy alone. Those animals treated with estrogen:anclrogen in ratio of 1 :2 (group C) and androgen alone (group D) displa.n'd marked prostatic weight gain. ·when estrogen: androgen were administered in a ratio of 2:1 (group 13), the prostatic weights re mained normal and WC'l't' comparable in size t(l those of intact uninjectecl control animals.
a,
276
M. W. WOODRUFF AND C. PEREZ-MESA
FIG. 2. Changes in prostatic histology with estrogen and androgen administration to hypophysectomized animals. A, appearance of prostate gland 2 weeks following hypophysectomy. Note marked atrophy, lining cells are low, acini small with an apparent increase in interacinar tissue. B, prostate following hypophysectomy and estrogen:androgen administration of 2:1 showing normal histologic appearance. C, prostate following hypophysectomy and estrogen showing dilatation of acini and conversion of tall columnar epithelium to low cuboidal in type. D, prostate of hypophysectomized animal treated with androgen. Note prostatic hyperplasia.
277
PROSTATIC MORPHOLOGY TABLE
3. Effect of estrogen and androgen on the prostatic weight of adrenalectomized animals
Group
Number of Animals
A
9 11
B C D E
10
11 10
Estrogen
Androgen
1nicrogranis
niicrograms
250 250 125 -
-
125 250 500
Adrenalectomized controls
Average Body Weight
Average Prostatic Weight
Prostatic Weight Body Weight
grants
milligrams
per cent
285.0 290.1 303.7 336.7 335.9
127.3 308.9 348.3 532.2 347.3
.045 .106 .115 .158 .103
I
Risto logically, the uninjected hypophysectomized animals (fig. 2, A) show a marked decrease in size of the individual acini. The lining cells are low cuboidal in type with closely packed nuclei making the cytoplasm barely visible. The interacinar tissue and the mast cells appear more prominent; however, further quantitative studies are necessary to determine the magnitude of these changes. These glands resemble the appearance of immature prostatic tissue. In those animals receiving estrogen: androgen in ratio of 2: 1 (fig. 2, B), the prostate glands appeared histologically normal. The acini were lined with tall columnar cells and in general appeared similar to those seen in the uninjected control animals (fig. 1, B). Hypophysectomized animals treated with estrogen following 2 weeks of supportive androgenic therapy displayed signs of atrophy as measured by dilated glands and lowering of the lining cells of the acini (fig. 2, C). Those animals injected with androgen alone showed marked prostatic stimulation as evidenced by increased glandular infolding, hyperplasia and increased mitosis (fig. 2, D). Prostatic response to androgen and estrogen in adrenalectomized animals. In this experiment, the animals were subjected to bilateral adrenalectomy and on the day following surgery started on the estrogen: androgen therapy for 2 weeks. Prostatic weight changes of the adrenalectomized animals following hormonal therapy are noted in table 3. Adrenalectomy alone without hormonal supplement had no effect on prosta tic weight (group E). Androgen administration caused an increase and estrogen a decrease of prostatic weight. Again noted was maintenance of normal size glands when estrogen and androgen were administered in ratio of 2: 1 in the absence of the adrenal glands.
Histologically, the untreated adrenalectomized control animals maintained normal microscopic appearance (fig. 3, A). Estrogen alone caused marked atrophy with dilatation of the glands and flattening of the epithelium (fig. 3, B). When the estrogen:androgen ratio was 1 :2 or greater, the prostate glands displayed evidence of hyperplasia including pseudostratification and vacuolization (fig. 3, C). Figure 3, D shows the histologic appearance of the prostate glands following administration of estrogen : androgen in 2 : 1 ratio following adrenalectomy. Again the prostate appearance is normal and microscopically indistinguishable from that of the uninjected intact control animal. Prostatic response of androgen and estrogen in castrated animals. The animals in this experiment had bilateral orchiectomy on the day prior to the initiation of their 2 week course of androgen and estrogen. The weight changes of the prostate gland are noted in table 4. Orchiectomized control animals receiving no supportive hormonal therapy (group E) showed a marked diminution in prostatic weight while those castrated animals that were maintained on androgen (group D) showed a moderate increase. When estrogen : androgen was administered in 2: 1 ratio, prostatic weight approached the lower limits of normal. Histologically, orchiectomy alone and in combination with estrogen was observed to cause marked atrophy, flattening of the lining epithelium with increased prominence of the mast cells and interglandular stroma (fig. 4, A and B). Castration and androgen (fig. 4, C) resulted in focal areas of hyperplasia. The prostates of those animals receiving estrogen: androgen in ratio of 2: 1 and 1 : 2 microscopically appeared normal with no evidence of atrophy or hypertrophy noted (fig. 4, D).
278
M. W. WOODRUFF AND C. PEREZ-MESA
Fm. 3. Changes in rat prostate histology with estrogen and androgen administration following bilateral adrenalectomy. A, rat prostate following adrenalectomy. Note normal histologic appearance. B, adrenalectomized rat prostate following estrogen, showing marked atrophy and flattening of acinar epithelium. C, androgen and adrenalectomy. Note evidence of hyperplasia. D, adrenalectomized animals receiving estrogen:androgen in 2:1 ratio. Note normal histologic appearance. DISCUSSION
This group of experiments supports the concept that estrogens produce atrophy and androgens hypertrophy of the prostate glands in both intact rats and in those previously hormonaly
modified by hypophysectomy, adrenalectomy and castration. The atrophy induced by estrogen, hypophysectomy and castration may be inhibited by the administration of androgen. Dy utilization of the rat prostate gland as a
PROSTATIC MORPHOLOGY
279
Frn. 4. Changes in rat prostate histology with estrogen and androgen following castration. A, prostate following orchiectomy showing marked atrophy. Note flattening of lining epithelium and increased prominence of interglandular stroma. B, rat prostate following combined orchiectomy and estrogen showing extreme atrophy similar to that noted with orchiectomy alone. C, prostate of animal receiving androgen following orchiectomy showing areas of hyperplasia. D, orchiectomized animal treated with estrogen: androgen in ra.tio of 2: 1. Note maintenance of normal prostatic histology.
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M. W. WOODRUFF AND C. PEREZ-MESA
TABLE 4. Effect of estrogen and androgen on the prostatic weight of orchiectomized animals Group
Number of Animals
A B C D E
11
14 10
13 15
Estrogen
Androgen
micrograms
micrograms
250 250 125
-
125 250 500 Orchiectomized controls
modality for biological titration, it was demonstrated that when estrogen: androgen were administered in ratio of 2: 1, the prostate gland was of normal weight and histology, even in the absence of the pituitary, adrenals or testes. This would indicate that the action of exogenous estrogen and androgen is a direct one on prostatic morphology, one which continues to be effective after the endogenous source of estrogen and androgen stimulation and production is ablated. The greatest degree of prostatic atrophy was obtained by hypophysectomy alone and demonstrates the important role of the pituitary gland in prostatic growth stimulation. Although the results obtained from animal experimentation are not necessarily applicable to man, these experiments would suggest that the greatest degree of prostatic growth inhibition can be obtained by hypophysectomy alone. Adrenalectomy alone effected no change in normal prostatic morphology. When adrenalectomy was combined with estrogen, prostatic atrophy ensued but not to the extreme degree noted by hypophysectomy. Orchiectomy induced about the same degree of prostatic atrophy as estrogen. When orchiectomy and estrogen were combined in the same animal, the changes in prostatic weight and histology over a 2 week period were not different than estrogen administration or castration alone. SUMMARY In four separate experiments, estrogen and androgen, alone and in combination, were administered to intact, hypophysectomized, adrenalectomized and castrated animals. The results tend to indicate that there is a direct independent antagonistic effect of exogenous estrogen and androgen on the growth and histology of the prostate gland. Normal prostatic morphology can be main-
Average Body Weight
Average Prostatic Weight
Prostatic Weight Body Weight
grams
milligrams
per cent
283.6 336.3 293.5 378.6 362.3
56.4 296.4 339.2 490.1 50.6
.019 .088 .116 .129 .014
tained following removal of these glands by the administration of estrogen and androgen in a ratio of 2: 1. Hypophysectomy alone effected the greatest degree of prostatic atrophy of all methods tested. REFERENCES FERGUSSON, J. D. AND PAGEL, W.: Some observations on carcinoma of the prostate treated with estrogens as demonstrated by serial biopsies. Brit. J. Surg., 33: 122, 1945. GRAYHACK, J. T., BUNCE, P. L., KEARNS, J. w. AND ScoTT, W.W.: Influence of the pituitary on prostatic response to androgen in the rat. Bull. Johns Hopkins Hosp., 96: 154, 1955. HUGGINS, C. AND CLARK, P. J.: Quantitative studies of prostatic secretion. J. Exper. Med., 72: 747, 1940. HUGGINS, C. AND RussELL, P. S.: Quantitative effects of hypophysectomy on testis and prostate of dogs. Endocrinol., 39: 1, 1946. DE JoNGH, s. E., KoK, D. J. AND VAN DER WOERD, L. A.: Paradoxe Wirkungen des Follikelhormons bei mannlichen Tieren. Arch. Internat. Pharmacodyn. et Ther., 58: 310, 1938. KoRENCHEVSKY, V. AND DENNISON, M.: Histological changes in the organs of rats injected with estrone alone or simultaneously with estrone and testicular hormone. J. Path. & Bact., 41: 323, 1935. MOORE, C.R., PRICE, D. AND GALLAGHER, T. F.: Rat-prostate cytology as testis-hormone indicator and prevention of castration changes by testis-extract injection. Am. J. Anat., 45: 71, 1930. NICOL, T., HELMY, I. D. AND ABOU-ZIKRY, A.: Histological explanation for the beneficial action of endocrine therapy in carcinoma of the prostate. Brit. J. Surg., 40: 166, 1952. PRICE, D.: Normal development of the prostate and seminal vesicles of the rat with study of experimental postnatal modifications. Am. J. Anat., 60: 79, 1936. SCOTT, w. w., HOPKINS, w. J., LUCAS, w. M. AND TESAR, C.: A search for inhibitors of prostatic growth stimulators. J. Urol., 77: 652, 1957. SELYE, H. AND ALBERT, S.: Effect of various steroids in intact male rats. Am. J. Med. Sc., 204: 876, 1942. WooDRUFF, M. W. AND UMIKER, W. 0.: The effect of estrogen and androgen on the rat prostate gland and testes. J. Urol., 84: 162, 1960. ZUCKERMAN, S. AND PARKES, A. S.: Effects of oestrone on prostate and uterus masculinus of various species of Primate. J. Anat., 70: 323, 1936.