Effects of mammalian gonadotropins (ovine FSH and LH) in female lizards

GENERAL

AND

COMPAR.4TIVE

Effects

14,

ENDOCRIh-OLfl(iY

!&lo6

of Mammalian and

(1970)

Gonadotropins

LH)

in Female

(Ovine

FSH

Lizards

P.41TL LIGHT Department

of Zoology,

linielersity

Reccivrd

oj

Califotnin,

Berkeley,

California

94730

June 27. 1969

The effects of ovine follicle stimulating hormone (FSH) and luteinizing hormone (LH) were studied in females of three lizard species-Ano/& carol&en&s, Uta stansburiana, and Sceloporrls occidentalis. In intact Anolis, that were physiologically hypophysectomized with respect to gonadotropins, doses of 10 gg FSH (12 mU) every other day produced normally enlarged ovaries, some ovulation and hypcrtrophy of the oviducts within two weeks. Combinations of 1 or 10 yg LH with this dose had no additional effect. A higher dose of FSH (50 fig) given alone or in combination with 50 gg LH for 13 or 29 days, caused an abnormal enlargement of the ovaries but seemed to block ovulation: oviducts were maximally enlarged in 13 days. LH alone (50 pg, 40 mu) for 13 or 29 days produced only slight ovarian and oviducal development, less than did 10 ,pg FSH for 14 days. The relative actions of FSH and LH in hypophysectomized Arwlis, were similar to those described above. Also, a very low dose (0.1 pg) of a purified FSH from Papkoff was found to promote ovarian development, oviducal enlargement, and ovulation in the hypophysectomized lizard. In hypophysectomized Uta and Sceloporus, 0.5-2 fig of the highly purified Papkoff FSH preparation caused ovulation in enlarged ovaries. The addition of 0.5 mU LH to these low doses of F$H had no effect, and LH alone was ineffective in producing ovulation. FSH also caused enlargement of the oviducts.

Studies of mammalian (ovine) gonadotropins in the male lizard demonstrated that both follicle stimulating hormone @‘SW and luteinizing hormone (LH, ICSH) are capable of promoting testicular growth, spermatogenesis, and interstitial cell activity in these reptiles (Licht and Pearson, 1969a). FSH is considerably more potent than LH with respect to all of these testicular activities. These results have provided important preliminary data for elucidating the gonadotropic regulation of reproduction in reptiles; for example, they suggest that reptiles may possessonly a single FSH-like gonadotropin complex (Licht and Pearson, 1969a). However, evaluation of these data is hindered by a lack of information concerning gonadotropit activities in the female reptile, especially since LH-activity is classically associated with ovulation. The present in98

vestigation examines the effects and relative potencies of ovine FSH and LH in follicular development, ovulation, and gonadal steroid secretion in several species of lizards, MATERIALS Care

of Condition

Lizards

AND and

Assay

METHODS of

Reproductive

Experiments were conducted with three species of iguanid lizards: (1) Anoh carolinensis from Louisiana, averaging about 2.Sg and 54 mm in snout-vent length ; (2) Uta stansburiana, from the Mojave Desert in California, averaging 32g and 48 mm; and (3) Sceloporus occidentalis, from around Sacramento, California averaging 9g and 65 mm long with a minimum snout-vent length of 66 mm. In Anolis each ovary normally contains only a single enlarged, yolky follicle. with the two ovaries ovulating alternately, and only one egg occurs in each oviduct at a time (Hamlett, 19521

FSH

In and

AND

LH

IN

Uta

and Sceloporus several follicles enlarge are shed simultaneously from each ovary. Lizards were maintained at body temperatures near their preferred levels-Anolis at 2930°C and Uta and Sceloporus at 33”C-with a 6 hr photoperiod. Mealworms and crickets and water were provided ad libitum. The Anolis were also hand-fed mealworms several times weekly, especially after hypophysectomy, to minimize starvation. Body weights and the condition of abdominal fat pads were used to evaluate the nutritional condition of all lizards at autopsy. Methods for removing the pars distalis (designated as hypophysectomy) and for histologically verifying the success of the operations are described in Licht and Pearson (196913). Reproductive responses were evaluated by weighing the paired ovaries and measuring the diameter of the follicles; the presence of oviducal eggs was taken a.~ an index of ovulation. Oviductal development served as an index of gonadal steroid secretion. The paired oviducts were weighed, embedded in Paraplast, and stained with hematoxylin and eosin for histological examination. Hormones Several preparations of ovine gonadtropins were employed. LH was obtained from the NIH (NIH-LH-Sll) and had a relative potency of 0.8 units/mg and a maximum FSH contamination of 0.016 units/mg. Preparations of FSH were obtained through the NIH or from Dr. Harold Papkoff. NIH-FSH-S6 had a mean relative potency of 1.24 units/mg and an LH contamination of 0.0045 units/mg. The Papkoff-FSH was a highly purified preparation that was found to have a potency of about 125 times the NIH-FSH-Sl standard in previous tests in male An&is carolinen& (Licht and Pearson, 1969a). The level of LH-activity in this preparation was assayed as 0.00017 units/mg (Papkoff, personal communication). Hormone doses (amount per injection and frequency of injection) varied and are detailed for the individual experiments below. In all cases, hormones were dissolved in distilled water and injected subcutaneously in 0.02 ml solution. Zntnct

An&is

carol&ens-k

The effects of NIH hormones were tested during November in intact but physiologically hypophysectomized Anolis. The ovaries and accessory structures are normally regressed between September and April, and previous experience in this laboratory indicated that the gonads remained quiescent during the winter if the animals were kept at 30°C with a short day-length (six

FEMALE

LIZARDS

99

hours). This lack of recrudescence was confirmed by the controls of the present study; thus, the lizards were considered to be “physiologically hypophysectomized” with respect to gonadotropins. Injections consisted initially of 1 and 50 pg FSH and LH alone or in combination given every other day. Five lizards of each group were sacrificed after two weeks. Since the 1 pg dose appeared ineffective at this time, the 1 pg dose of FSH or FSH f LH was increased to 10 pg of each, and the 1 pg of LH was changed to 10 pg FSH + 1 pg LH. The higher doses (50 pg) were continued unchanged. All of the remaining animals were sacrificed after two additional weeks of injection (i.e., after a total of 14 injections in 28 days). Hvpophysectomized

Anolis

carolinensk

A second experiment was undertaken with surgically hypophysectomized AnoC in order to eliminate the possibility of an influence by endogenous gonadotropins. This study was begun in the first week of April. Autopsy of 10 animals at the beginning of the experiment showed that follicles were undeveloped (<2 mm and lacked yolk) and oviducts atrophic. Injections were made every other day for 21 days at the following doses: 0.1 gg Papkoff-FSH; 1, 10, and 106 pg NIH-FSH; 1 and 10 gg each of NIH-FSH and LH; 10 pg LH. Hypophysectomized and Sceloporus

Uta stansburiana occidentalis

Studies with the Uta and Sceloporus-in April-were focused primarily on determining whether FSH alone was capable of stimulating ovulation. For this purpose, all animals were hypophysectomized and the highly purified Papkoff FSH preparation was used in low doses. One group of Utu was injected with 0.01 /~g FSH daily for 1 week followed by 05 gg FSH daily for the second week. A second group received 0.1 gg FSH daily for the first week and 2.0 pg for the second week. A third received 0.5 mU NIH-LH for the entire two weeks; this dose of LH is about 3,006 times the LH contamination in 1 pg of the Papkoff FSH. A fourth group served as untreated controls. The condition of the ovaries in the Sceloporus was not determined at the time of hypophysectomy but their appearance at autopsy suggested that follicles varied from undeveloped to near ovulation. These lizards were injected every other day for 10 days with 2 pg Papkoff FSH, 2 pg Papkoff FSH+0.5 mU LH, 0.5 mU LH, or 100 mU LH.

100

PAUI.

TJ(‘HT

RESULTS

Intact (Physiologically mized) Ano1i.s

Hypophysecto-

Ovarian and oviducal weights in intact Anolis after hormonal treatment for 13 or 28 days in November are shown in Table 1. In animals examined at the beginning of the experiment, the ovaries and oviducts were undeveloped and there was no change in the saline injected controls, indicating the absence of endogenous gonadotropins. Responses were relatively uniform within each hormone-treated group. In general, FSH was clearly more effective in promoting gonadal development and enlargement of the oviducts than was LH. Increased oviduct weights in hormone-treated animals was in all cases associated with pronounced histological hypertrophy of the oviducal tissues as illustrated for Sceloporus below. The low doses (1 pg) of FSH and LH were essentially ineffective with respect to EFFECTS

(NIH)

OF OVINE INT.4CT

FSH

(PHYSIOLOGICALLY

AND

TABLE I LH ON OVARY

ld days (6 inject,ions) Control l/szLH 50 rg LH 1 rg FSH 50 fig FSH 1 fig FSH + 50 pg FSH + $7 days Control 50 ,.eg LH 10 pg FSH* 50 /ig FSH 10rgFSH+lI*gLIP 10 rg FSH + 50 fig FSH +

AND

N

ovary (mg)

OVIDUCT

Anolis

HYPOPRISECTOMIZFJD)

Paired Treatment”

the variables examined. The high dose of FSH (50 pg), alone or in combination with 50 pg LH, produced pronounced follicular enlargement within 12 days, the oviducts were maximally enlarged, and one of the females treated with FSH alone had ovulated at this time. However, there was no further ovulation in these two groups during the next 14 days of treatment. Instead, at 28 days, the ovaries in all of the 15 individuals of the two groups receiving 50 pg FSH appeared abnormal in that they contained numerous (4-8) enlarged yolky follicles (6-7 mm). This condition is reflected in the high ovarian weights (Table 1). The ovaries completely filled and extended the body cavity. Females treated with 10 pg FSH for the last two weeks (either alone or with 1 or 10 Pg LH) also had significantly enlarged ovaries and oviducts, but only 1 or 2 enlarged follicles (i.e., the normal compliment) were present in each ovary. Furthermore, 7 of these 21 lizards f3 of 6 receiving

wt,.

1 Ilg LH 50 pg LH

5 5 5 5 5 5 5

8.4 6.6 14.2 10.5 173.4 11.9 125.1

f III k * zk + 5

1.6e 1.3 1.2 1.1 18.3d 1.6 23.4

10 rg LH* 50 rg LH

7 9 6 8 7 8 7

10.1 99.8 121.5 286.2 82.2 106.7 346.0

* f + * rt f f

2.1 25.6 21.2d 25.4 20.7d 19.2d 41.4

DEVELOPMENT

IN

carolinensis

No. ovulat,ed

1

3 1 3

Paired

oviduct

wt.

Crng) 16.3 14.9 28.5 16.5 50.7 25.4 57.5

f l.le zk 3.6 3~ 2.8 fr 2.8 * 4.8 k 2.8 * 2.0

17.5 32.2 51.4 54.3 39.0 47.6 52.2

z!Y2.1 + 4.5 f 4.8 f 6.6 f 4.0 + 3.5 31 5.1

0 Injections were made every other day, starting on November 7, at 30°C with 6 hours of light daily. * These doses were given only for the last 13 days (days 14-27); doses were lower (1 pg) during t’he first 14 days. c This group received only 1 fig LH for the first 17 days and the 10 rg FSH was included between 17-27 days. d Individual ovary weights were not corrected for losses due to the l-2 ovulat,ed follicles. e Mean + SE.

FSH

AND

LH

IN

FEMALE

101

LIZARDS

FSH alone and 4 of 15 receiving FSH + LH) had ovulated by 28 days. No significant differences in oviducal weight were observed between animals treated with only FSH, or FSH + LH. The slightly smaller size of ovaries and oviducts in the 10 fig FSH + 1 ,ug LH group is probably due to the fact that the 10 pg FSH injections in this group were not started until three days after they were begun in the other two. The high dose of LH (50 pg) had only a slight effect on ovarian and oviducal weights (p < .05) at 13 days. These structures were considerably enlarged but still less developed at 28 days than in the group injected with 10 pg FSH for only the last two weeks (Table 1).

FSH and LH, could be made easily by the size and appearance of the follicles and oviducts as indicated in Table 2. Autopsy of individuals dying during the five days before autopsy (between 15 and 20 days of tre tment) indicate the same general trends J+ru s wn, by the animals autopsied at 21 days (see nuniervbk in parentheses in Table 2). Since the majority of animals, including most that died during treatment, contained dissectable abdominal fat pads, errors due to starvation should not be serious. In general, the relative potencies of FSH and LH in hypophysectomized Anolis were similar to those obtained with the intact, physiologically hypophysectomized controls, although the 1 pg dose of FSH was more effective in the former. HypophysecHypophysectomized Anolis tomized controls had undeveloped follicles Unfortunately, the reduction in sample and oviducts. Low doses of NIH-FSH (1 or size, due to some mortality in all groups, 10 pg) promoted follicular development and the variation in body size of animals and oviducal enlargement and ovulation occurred in two individuals. The addition remaining at 21 days precludes meaningful quantitative treatment of ovarian and ovi- of LH to these doses had little effect. The ducal weights. However, a qualitative as- high dose of FSH (100 pg) caused abnormal numbers of follicles to enlarge but sessment of the response of these hypophysectomized females, to the various doses of no ovulation occurred. Ovaries of the two EFFECTS

TABLE 2 OF OVINE FSH AND LH ON OVARY AND OVIDUCT DEVELOPMENT SURGICALLY HYPOPHYSECTOMIZF,D (Hx) Anolis carolinensis

IN

Ovaries” Follicles undeveloped

Treatment” Hz Control 10 /.,g LH 0.1 pg Papkoff 1 rg NIH-FSH 10 rg NIH-FSH 100 pg NIH-FSH lrgFSH+lcrgLH

7 (8) 4 (7) FSH

1

1 (4)

-

Follicles enlarged

-

4 3 4 2 3

No. ovulated

(5) (4) (6) (5) (4)

2 1 1

-

Oviducts enlargedc

3

3 3 2 3

a Hormones were given every other day, at the indicated doses, for 21 days starting on the day after hypophysectomy, April 11. b Ovaries were considered undeveloped when follicles were clear and <2 mm diameter, and paired ovaries weighed < 18 mg; enlarged ovaries contained one or more yolky follicles (ranging from 4-6 mm in diameter) and the paired ovaries weighed 40-300 mg. The numbers in each category at the end of 21 days are given; numbers in parentheses show the total number of each type including animals that died in the five-day period preceding autopsy. 0 Oviducts were considered enlarged if the weight of the paired oviducts exceeded 19 mg (ranging from 19-50 mg), t,hese values corresponded t,o histjological signs of epithelial hypertrophy.

I’AUL

LIGHT

FIG. 1 Photographs of hypophysectomieed -1nolis curolirxnsis to illrrstrute i he effects of a relatively high dose of ovine FSH. Both animals weighed ca. S g and measured 54 mm in sno\it-vent 1engt.h. The female on the left was an uninjected control 21 days after hypophysectomy: t,he ovaries were undeveloped (combined weight = 10 mg), the oviducts atrophic (combined weight = 15.5 mg), and the abdominal fat bodies were large, weighing 110 mg. The female on the right was injected with 100 fig (1% mU) NIH-FSH every ,other day for 21 days aft.er hypophysectomy: the ovaries contained a t.otal of six enlarged yolky follicles (2, 5 mm; 2, 4 mm; 2, 3 mm in diameter) and weighed 245 mg; the oviducts weighed 45 mg. There were no dissectable fat bodies. Abbreviations: ova, ovaries; Ovid, oviduct,s; ,ft hd, fat bodies.

individuals killed at 21 days weighed 245 and 300 mg and each contained four enlarged yolky follicles (see Fig. 1). The single dose (10 pg) of LH alone had no TABLE RESPONSES OF THE OVARIES AND OVIDUCTS LH (NIH) IN HYPOPHYSECTOMIZED Ovarian

effect on ovarian growth although the oviducts were enlarged in a few cases. A very low dose of highly purified Papkoff FSH (0.1 pg) was effective in promoting ovar3 TO MAMMALIAN (Hx) Sceloporus

FSH (PAPKOFF) cecidentalis

folliclesb

ANU

Oviducts ___-

Undeveloped

Treatment.” Hx 0.5 100 2 2

Controls mLJ LH mU LH pg FSH pg FSH

+ 0.5 mU

LH

2 s S 4 1

Enlarged 6 5 3 5 7

NO. ovulat.ed 2 -

No. hypertrophied 0 I ‘2 6 7

Weight 56.4 58.1 71.9 102.0 68.2

(mg) z! 3.9d z!s-8.1 + 13.2 f 25 + 8.3

n Animals were injected every other day for 10 days starting after hypophysectomy (Hx) on April 6. 6 Follicles were considered undeveloped when the follicles were clear and less than 3 mm. Enlarged ovaries contained up to 8 yolky follicles (4-7 mm). c Oviducts were considered hypertrophied if the epithelium was conspicuously thickened and glandular (Fig. 4-5). d Mean f SE for fresh weight of paired oviducts.

FSH

AND

LH

IN

FEMALE

ian growth, ovulation and oviduct development; the effects were equivalent to those obtained with 10 pg (12 mu) NIH-FSH (Table 2). Hypophysectomized

Uta and Sceloporus

Variability in the conditions of the ovaries and oviducts among both control and hormone-treated Sceloporus and Uta precluded meaningful comparisons of organ weights. A qualitative evaluation of these data (presented in Tables 3 and 4) indicates that FSH stimulates both ovulation and oviducal development. One of the Sceloporus treated with the high dose of LH (100 mu) contained a collapsed ovarian follicle and a yolky substance was found in the abdominal cavity but there was no ovum in either oviduct. However, normal ovulation was observed in only the FSH treated group; two of the nine lizards contained several normal appearing (but as yet unshelled) eggs in each oviduct. The actions of hormone-treatment, especially FSH, was more distinct with regard to oviducal development. Although there were no significant differences (p > 0.05) among the average weights of the oviducts in the five groups, histological examination revealed a marked dichotomy in the oviducts. The epithelium of TABLE RESPONSES

OF THE

LH

OVARY

(NIH)

103

LIZARDS

even the largest control oviducts (70 mg) was clearly atrophic with sparse and involuted glands (Figs. 2-3), whereas a pronounced hypertrophy of this tissue was evident in almost all of the FSH-treated animals, although the weights of some -oviducts were the same or even less than in controls (Figs. 2-5). It seems likely that the ovaries and oviducts of control and LH treated animals had been developed at the time of hypophysectomy and were regressing. Using the presence of the enlarged epithelium as an index of oviducal stimulation (Figs. 4-5), a distinct FSH-effect is observed (Table 3). A Chi-square test indicates a highly significant difference (p < 0.001) in the frequency of hypertrophied oviducts between the combined FSHtreated groups and combined control and LH treated groups; comparison of the two FSH-treated groups combined versus the two groups treated with only LH combined also shows a significant difference (p < 0.02) in this respect. Among the hypophysectomized Uta (Table 4), ovulation occurred with FSH but not with LH (FSH + LH was not tested). There were no significant differences in oviducal weights among groups, although the weight of FSH-treated oviducts averaged almost twice that of the 4

AND OVIDUCTS TO MAMMALIAN’ FSH IN HYPOPHYSECTOMIZED Uta stunsburiana

(PAPKOFF)

AND

--

Oviducts Ovarian Treatment0 Hx 0.5 0.01 0.1

wntrol mU LH and 0.5 pg FSH and 2.0 Bg FSH

Undeveloped 1 3 1

folliclesb Enlarged 6 3 5 5

No. ovulatedc 2 3

No. hypertrophiedd 3 1 4 6

Weight 16.8 15.2 35.4 31.3

(mg) + 2.3” f 2.9 31 8.8 f 6.6

a Animals were injected daily for 14 days after hypophysectomy (Hx) starting in April. FSH changed from the low to high value at the end of 7 days. b Follicles were considered undeveloped when they lacked yolk and were less than 3 mm in Enlarged ovaries contained 34 yolky follicles over 4 mm in diameter. The numbers of individuals category are shown. c Individuals containing one or more eggs in the oviduct. These are also included under those larged” ovaries. d Oviducts were judged to be hypertrophied on the basis of histological appearance; weight of oviducts usually exceeded 20 mg when hypertrophied. 6 Fresh weight-s of paired oviducts showing Mean f SE.

doses were diameter. in each with

“en-

the paired

FIGS. 2-5. Sections of the middle section of the oviduct,s (8 ,.L in thickness and st:Gned with henmtoxylineosin) from hypophysectomized Sceloporus kept at 33°C for 10 days. Scale shows 100 micra for all. Fig. 2. iLIaximally regressed oviduct (paired weight, = 15 mg) of hppophysectomized control. Fig. 3. Heavieat ovidrlct (paired weight, = 70 mg) among the hypophysectomized controls; epithelium is in the process of regression. Fig. 4. Relatively small oviducts (paired weight = 66 mg) from the hypophysectomized group receiving 3 rg Papkoff FHH every other day: the epit,helium is considerablp more developed than in the larger oviduct,s of the hypophysectomized controls. Fig. 5. Fully hypertrophied ovidrlct (paired weight = 1.57 mg) from a hypophysectomiaed animal treated with 2 pg Papkoff FSH every other day.

FSH

AND

LH

IN

others. The marked dichotomy in histological appearance reflecting stimulation discussed for Sceloporus was also evident in Uta. Several of the controls still had enlarged oviducts, but on the basis of histdogy, the frequency of hypertrophied oviducts among the two FSH-treated groups was significantly greater (p < 0.02) than among the control and LHtreated groups combined. DISCUSSION

These studies indicate that both FSH and LH can stimulate gonadal growth and steroid secretion in female lizards, but that FSH is considerably more potent in both regards. FSH also appears able to induce normal ovulation, whereas this was not observed with LH. It seems unlikely that the broad actions of FSH were influenced by or dependent on LH contamination, since all of these actions were obtained with the very low doses (0.1-2 pg) of the purified Papkoff-FSH. Doses of LH eevera1 orders of magnitude higher than the low level of contamination expected in this FSH had almost no effect on the ovary of the lizard, and there was little if any synergism between FSH and LH. The possibility that FSH contamination influenced the response to high doses of LH is perhaps more likely in view of the lizards’ high sensitivity to FSH. Thus, the ovine FSH molecule appears capable of stimulating all aspects of ovarian function in the lizard, and, in fact, FSH may be indispensable for certain features such as ovulation. In the male lizard, Anolis carolinensis, stimulation of gonadal steroidogenesis, as judged by the development of epididymis and renal sex segment, appeared to require higher doses of gonadotropin than were required for testicular growth and spermatogenesis (Licht and Pearson, 1969a). The relative sensitivities of follicular enlargement and steroid secretion to gonadotropins are less distinct in the female Anolis, although in one case (50 pg LH at 12 days) a significant enlargement of the oviduct occurred before follicular enlargement (Table II.

FEMALE

LIZAIlDS

105

Although the results of gonadotropin treatment in hypophysectomized Uta and Sceloporus were more variable than in Anoh, the relative potencies and actions of the ovine FSH and LH appear to be similar in all three species. The large variability in the responses of the Uta and Sceloporus are difficult to interpret without additional information on the reproductive biology of these species, e.g., normal rate of follicular and oviducal development, age of sexual maturity, regularity of annual egg laying, etc. Ferguson (1966) found that three injections of 250 ag FSH (potency unstated) produced follicular enlargement within 10 days in intact Uta stansburiana (from Texas) during December when the gonads were initially involuted, and the response was relatively uniform among his experimental animals. Therefore, the data for all the species examined are consistent, indicating that. FSH may stimulate follicular enlargement, ovulation and oviducal enlargement (steroidogenesis) while LH is relatively ineffective in these respects. Studies with female Anolis are particularly interesting with regard to the dose-response relations for the gonadotropins. The surgically hypophysectomized animals responded to lower doses of FSH than did the intact, physiologically hypophysectomized animals, but the rate of gonadal development was somewhat lower in the former. The rate of egg production in the intact FSH-treated Anolis was very similar to the natural rate of egg production observed in this species (Hamlett, 1952). The slower rate of foIlicular development in hypophysectomized Anolis might reflect a general systemic deterioration or the importance of other endocrine glands. Of particular interest in both intact and hypophysectomized Anolis is the abnormal action of high doses of FSH. Whpreas the relatively low doses of NIH-FSH (l-10 pg) appeared to cause normal follicular growt,h and ovulation, high doses (S&l00 pg) appeared to “over-stimulate” the ovary with the production of abnormally large numbers of follicles t’hat appeared to he

106

PAL-I,

“trapped” in the ovary. Thus, endogenous gonadotropin levels in female Ano& are most closely mimicked by the 12 mU dose of ovine FSH. This is the same dose that was found to mimic endogenous gonadotropic activity in the male An&s (Light and Pearson, 1969a). The estimate of the relative potency of the Papkoff-FSH in the female An&is (about 125 X NIH-FSH-Sl since the effects of 0.1 ,pg Papkoff-FSH was equivalent to 10 ,ug NIH-FSH-S6, Table 2) is the same as was obtained in studies with males of this lizard (Licht and Pearson, 1969a). This estimate is several times higher than that obtained by bioassay of the Papkoff preparation in the rat, using the SteelmanPohley test (Papkoff, 1966). The absolute sensitivity of the female AnAs to FSH (as judged by the minimal effective dose) is almost identical to that observed in the male (Licht and Pearson, 1969a). In general, the gonadotropic requirements, with respect to ovine FSH and LH, of the reproductive system of the female lizard, are the same as those observed in the male lizard, and thus support the possibility that the lizards may have only a single FSH-like gonadotropin (or gonadotropin-complex). These results do not support the scheme commonly postulated for the control of reproductive events in reptiles (Grignon and Grignon, 1965) ; namely, that there is a release of two separate gonadotropins (an FSH and LH) which differentially control follicular developof sexual accessory ment, enlargement structures and ovulation. Note added in proof: Jones (J. Exp. Zool.. 171, 217-221 (1969)) reported that 1 I.U. (30 Bg) NIHFSH stimulated ovarian growth and oviduct enlargement in intact skinks. Lygosoma laterale, whereas 1 I.U. (0.7 pg) NIH-LH or 1 I.U. HCG had no effect on these organs; tests were not con-

LIGHT

ducted more,

long enough to study ovulation. E’uthcrLH antagonized the effects of FSH. These results provide further evidrnce for the conclusions regarding thr broad spcctt’um of nctivit? exhibited by FSH in lizards. ACKNOWLEDGMENTS I wish to thank technical assistance

Mrs. Anita Ii. Pearson for and advice in the preparation of this manuscript. I am also indebted to Miss Lynn Bengston for technical assistance. Dr. Harold Papkoff of the Hormone Research Laboratory of the University of California and the Endocrinology Study Section of the U. S. Public Health Service generously provided the hormones used in this study. This work was supported in part by grant GB-7306 from the National Science Foundation and by funds from a Biomedical Research grant from the University of California. REFERENCES G. W. (1966) Effect of follicle-stimulating hormone and testosterone proprionate on the reproduction of the side blotched lizard, Uta stansburiana. Copeia 196% 49.5498. GRIGNON, G., AND GRIGNON, M. (1965). Variations cycliques de l’activits des glandes endocrines chea les reptiles. Proc. 2nd Int. Congr. Endocrinol. Part I., ~1,. 106-113. Excerpta Med. T\‘o. 83. HAMLET-T, G. W. D. (1952). Notes on breeding and reproduction in the lizard Ano1i.s carolinenb-6. Copeia 1952, 183-185. LICHT, P., AND PEARSON, A. K. (1969a). Effects of mammalian gonadotropins (FSH and LH) on the testes of the lizard Analis carolinensis. Gen. Comp. Endocrinol.. in press. LICHT, P., AND PEARSON, A. (196913). Effects of adenohypophysectomy on testicular function in the lizard Ann& carolinensis. Viol. Reprod. 1, 107-119. PAPKOFF, H. (1966). Recent studies on the purification and properties of ovine, bovine, and human interstitial cell stimulating hormone (ICSH, LH) and ovine follicle stimulating hormone (FSH). Proc. 6th Pan-Am. Congr. Endoc&ml., Mexico City. pp. 334339. Excerpts Med. No. 112.

FMMXJSON,