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249. Dietary influences on plasma levels of testosterone, 5 α-dihydro-testosterone and prolactin in male rats
lxxxiii
Abstracts 247.
ON THE REGULeTjON
OF THE
E2TRAMUSTINE
BINDING
PROTEIN
IN IHE
PROSTATIC
SELL
P. , Carlstr8m, K. , Forsgren, B. , Hsgberg, B. , and Pousette, A. ’ , gjiirk, ustafsson, J.-A. . 4 F 3Dept. of Medical Nutrition and Hormone baboratory, of Clinical Chemistry, Dept. Karolinska Institutet, Huddinge Univ. Hospital, S-141 86 Huddinge, and Leo Research Laboratories, Box 941, S-251 09 Helsingborg, Sweden. Estramustine binding protein (EMBP), also called Prostatic Secretion Protein, is an androgen sensitive protein making up about 20% of the protein content in rat ventral We have purified EMBP and studied its hormonal regulation using prostate cytosol. immunological methods. Using specific antibodies we have studied the synthesis and the purified protein inhibits the nuclear uptake secretion of EMBP. Interestingly, as well as the binding to DNA-cellulose of the androgen receptor. Based on these studies it is tempting to speculate that the concentration of EMBP may serve as an intracellular regulator of androgen uptake in the cell nuclei and thereby also of androgen action in the prostatic cell.
248.
Role of Prolactin(PRL)in regulation of the nocturnal eurm of teetoeteronr(T)ia the bonnet monkey(Mececa radi&a)by A.Jqgannedha Rao end N.R.Moudgd, Center for Mv.Study in Reprod.biol., Leb.Endo.Biochem., Indim Institute of Sci8nce. Bmgalore 560 012, India. Earlier studies from this lebordory have shown thet adult male bonnet monkeys exhibit nychthemrel rhythmicity la the secretion of eerum 'T' the levele reehlng peek by 22OOhr. Of the gonedotropine cnelyeed only serum PRL showed a concommitent increme with T(Biol.of Reprod. 24,814, 1981). In the present study mMinietretion of lrgobromocryptin (EBC) either by i.v.route(2mg)or by naeel l pr~(100~)reeulted in blockade of nocturnal increase of both PRL end T(Controle T-18.6ng/ml: PRL 130=29ng/ml: EBC treated T-2.2&1.2ng/ml; PRL n.d.to 15nng/ml). Adminietretion of N oPRL could not reverse the effect of EBC. Although, increaeed serum PRL induced by injection of Chlorprommine did not result in increase in serum 'T' during the dey time, the nocturnel 'T' surge could not be obeeerved. EBC treeted monkeys, however, ehowed normal testosterone response to exogenous hCG. These IeSUlte a0 SwgeStive of high levels of PRL me&in6 reeponeiveneee of testes to tonic levels of serum IX. (Aided by grant8 from ICMR, Kew Delhi, WHO, Geneva eld FPF, India).
249.
DIETARY INFLUENCES ON PLASMA LEVELS OF TESTOSTERONE, 5 a-DIHYDRO-TESTOSTERONEAND PROLACTIN IN MALE RATS Bunnik, G.S.J., Bosland, M.C., Prinsen, M.K. and Hidajat, E. Institute CIVO-Toxicology and Nutrition TNO,i!eist,TheNetherlands Diet may influence steroid hormone status in men (Hill, P.et'al., Cancer Res. 39 (1979) 5105).High dietary levels of fat are indicated to be associated with elevated plasma prolactin (Prl) in male rats (Cohen et al .,Proc.6lst.Anm.MeetingEndocr.Soc. (1979) p.291. We studied dietary influences on plasma concentrations of testosterone CT),5 a-dihydrotestosterone (DHT) and Prl in male Wistar rats as measured by RIA. Equicaloric semisynthetic diets were fed to groups of 10 rats for 4,8,16 and 32 weeks from weaning. The diets varied in type and amount of fat, protein and carbohydrate. One group was restricted in the intake of energy from carbohydrates. Results indicated complex interactions of dietary variables with plasma levels of T,DHT,and Prl and the ratio T/DHT in relation to the time for which the diets were fed and the age of the animals. The balance between animal source protein and vegetable source protein as well as the balance between polyind oligosaccharides appeared to be important factors rather than the absolute amounts ingested. To a lesser extent fat levels in the diet and degree of saturation of fat seemed to be of some importance,as was restriction of energy intake from carbohydrates.Theratio of T/DHT was often influenced,indicating dietary influences on DHT formation/metabolismrather than on production/secretionof T.
Abstracts 247.
ON THE REGULeTjON
OF THE
E2TRAMUSTINE
BINDING
PROTEIN
IN IHE
PROSTATIC
SELL
P. , Carlstr8m, K. , Forsgren, B. , Hsgberg, B. , and Pousette, A. ’ , gjiirk, ustafsson, J.-A. . 4 F 3Dept. of Medical Nutrition and Hormone baboratory, of Clinical Chemistry, Dept. Karolinska Institutet, Huddinge Univ. Hospital, S-141 86 Huddinge, and Leo Research Laboratories, Box 941, S-251 09 Helsingborg, Sweden. Estramustine binding protein (EMBP), also called Prostatic Secretion Protein, is an androgen sensitive protein making up about 20% of the protein content in rat ventral We have purified EMBP and studied its hormonal regulation using prostate cytosol. immunological methods. Using specific antibodies we have studied the synthesis and the purified protein inhibits the nuclear uptake secretion of EMBP. Interestingly, as well as the binding to DNA-cellulose of the androgen receptor. Based on these studies it is tempting to speculate that the concentration of EMBP may serve as an intracellular regulator of androgen uptake in the cell nuclei and thereby also of androgen action in the prostatic cell.
248.
Role of Prolactin(PRL)in regulation of the nocturnal eurm of teetoeteronr(T)ia the bonnet monkey(Mececa radi&a)by A.Jqgannedha Rao end N.R.Moudgd, Center for Mv.Study in Reprod.biol., Leb.Endo.Biochem., Indim Institute of Sci8nce. Bmgalore 560 012, India. Earlier studies from this lebordory have shown thet adult male bonnet monkeys exhibit nychthemrel rhythmicity la the secretion of eerum 'T' the levele reehlng peek by 22OOhr. Of the gonedotropine cnelyeed only serum PRL showed a concommitent increme with T(Biol.of Reprod. 24,814, 1981). In the present study mMinietretion of lrgobromocryptin (EBC) either by i.v.route(2mg)or by naeel l pr~(100~)reeulted in blockade of nocturnal increase of both PRL end T(Controle T-18.6ng/ml: PRL 130=29ng/ml: EBC treated T-2.2&1.2ng/ml; PRL n.d.to 15nng/ml). Adminietretion of N oPRL could not reverse the effect of EBC. Although, increaeed serum PRL induced by injection of Chlorprommine did not result in increase in serum 'T' during the dey time, the nocturnel 'T' surge could not be obeeerved. EBC treeted monkeys, however, ehowed normal testosterone response to exogenous hCG. These IeSUlte a0 SwgeStive of high levels of PRL me&in6 reeponeiveneee of testes to tonic levels of serum IX. (Aided by grant8 from ICMR, Kew Delhi, WHO, Geneva eld FPF, India).
249.
DIETARY INFLUENCES ON PLASMA LEVELS OF TESTOSTERONE, 5 a-DIHYDRO-TESTOSTERONEAND PROLACTIN IN MALE RATS Bunnik, G.S.J., Bosland, M.C., Prinsen, M.K. and Hidajat, E. Institute CIVO-Toxicology and Nutrition TNO,i!eist,TheNetherlands Diet may influence steroid hormone status in men (Hill, P.et'al., Cancer Res. 39 (1979) 5105).High dietary levels of fat are indicated to be associated with elevated plasma prolactin (Prl) in male rats (Cohen et al .,Proc.6lst.Anm.MeetingEndocr.Soc. (1979) p.291. We studied dietary influences on plasma concentrations of testosterone CT),5 a-dihydrotestosterone (DHT) and Prl in male Wistar rats as measured by RIA. Equicaloric semisynthetic diets were fed to groups of 10 rats for 4,8,16 and 32 weeks from weaning. The diets varied in type and amount of fat, protein and carbohydrate. One group was restricted in the intake of energy from carbohydrates. Results indicated complex interactions of dietary variables with plasma levels of T,DHT,and Prl and the ratio T/DHT in relation to the time for which the diets were fed and the age of the animals. The balance between animal source protein and vegetable source protein as well as the balance between polyind oligosaccharides appeared to be important factors rather than the absolute amounts ingested. To a lesser extent fat levels in the diet and degree of saturation of fat seemed to be of some importance,as was restriction of energy intake from carbohydrates.Theratio of T/DHT was often influenced,indicating dietary influences on DHT formation/metabolismrather than on production/secretionof T.