Effects of prolactin on androgen metabolism in androgen target tissues of immature rats

Testosterone metabolism in androgen target tissues of immature Wistar male rats was studied after the injection of ovine PRL (oPRL) or after changes in PRL levels induced by the administration of dopaminergic agonists or antagonists. Treatment with oPRL (500 μg/rat-day) for 10 days, starting on day...

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Autores principales: Barañao, José Lino S., Calvo, Juan Carlos, Charreau, Eduardo Hernán
Publicado: 1981
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rat
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00137227_v109_n6_p2188_Baranao
http://hdl.handle.net/20.500.12110/paper_00137227_v109_n6_p2188_Baranao
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spelling paper:paper_00137227_v109_n6_p2188_Baranao2023-06-08T14:36:02Z Effects of prolactin on androgen metabolism in androgen target tissues of immature rats Barañao, José Lino S. Calvo, Juan Carlos Charreau, Eduardo Hernán androgen androstane derivative androstanolone c 14 bromocriptine dopamine receptor luteinizing hormone prolactin radioisotope sulpiride testosterone testosterone c 14 unclassified drug age animal experiment article drug metabolism endocrine system male genital system prostate rat seminal vesicle testis Androgens Animals Bromocriptine Genitalia, Male Male Organ Size Pimozide Prolactin Rats Rats, Inbred Strains Sexual Maturation Sulpiride Testis Testosterone Testosterone metabolism in androgen target tissues of immature Wistar male rats was studied after the injection of ovine PRL (oPRL) or after changes in PRL levels induced by the administration of dopaminergic agonists or antagonists. Treatment with oPRL (500 μg/rat-day) for 10 days, starting on day 30 of age, caused a significant increase in testes and sex accessory organ weights and a concomitant augmentation in prostatic 5α-reductase activity. This effect, however, was not observed in epididymis and seminiferous tubules (ST). Daily administration of bromocriptine (3 mg/kg BW) using the same injection schedule suppressed endogenous PRL without altering serum LH levels. Testis and sex accessory organ weights and serum 5α-androstane-3α, 17β-diol levels were reduced in the animals treated with this dopaminergic agonist. These changes were associated with a significant decrease in 5α-reductase activity in both prostate gland and ST. Treatment with the dopaminergic antagonist sulpiride (43 mg/kg BW) during the same period induced a 4-fold increase in serum PRL levels, whereas LH levels remained unaltered. Although serum concentrations of testosterone (plus dihydrotestosterone) and 5α-androstane-3α, 17β-diol were significantly higher in sulpiride-treated rats, no significant changes in testis and sex accessory organ weights were detected in these animals. Sulpiride was unable to stimulate A4-5α-reductase activity in the prostate gland. Treatment with sulpiride or bromocriptine caused a significant increase in the 3α-hydroxysteroid dehydrogenase (3α-HDH) activity in ST. This effect was concomitantly seen in the ST and epididymides of 25-day-old rats after bromocriptine administration for 5 days. Another dopaminergic antagonist, pimozide, was also able to induce a similar increase in 3α-HDH activity in the ST and epididymis, even though chronic administration of this drug produced a significant decrease in serum PRL levels. The diminution in enzyme activity observed after the suppression of endogenous PRL levels by bromocriptine suggests that this hormone is involved in the control of Δ4-5α-reductase in the prostate and ST. However, induction of similar changes in the 3α-HDH activity by two dopaminergic agents with opposite effects on plasma PRL levels indicates the possibility of direct actions of these drugs on androgen target tissues. (Endocrinology 109: 2188, 1981). © 1981 by The Endocrine Society. Fil:Barañao, J.L.S. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Calvo, J.C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Charreau, E.H. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 1981 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00137227_v109_n6_p2188_Baranao http://hdl.handle.net/20.500.12110/paper_00137227_v109_n6_p2188_Baranao
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic androgen
androstane derivative
androstanolone c 14
bromocriptine
dopamine receptor
luteinizing hormone
prolactin
radioisotope
sulpiride
testosterone
testosterone c 14
unclassified drug
age
animal experiment
article
drug metabolism
endocrine system
male genital system
prostate
rat
seminal vesicle
testis
Androgens
Animals
Bromocriptine
Genitalia, Male
Male
Organ Size
Pimozide
Prolactin
Rats
Rats, Inbred Strains
Sexual Maturation
Sulpiride
Testis
Testosterone
spellingShingle androgen
androstane derivative
androstanolone c 14
bromocriptine
dopamine receptor
luteinizing hormone
prolactin
radioisotope
sulpiride
testosterone
testosterone c 14
unclassified drug
age
animal experiment
article
drug metabolism
endocrine system
male genital system
prostate
rat
seminal vesicle
testis
Androgens
Animals
Bromocriptine
Genitalia, Male
Male
Organ Size
Pimozide
Prolactin
Rats
Rats, Inbred Strains
Sexual Maturation
Sulpiride
Testis
Testosterone
Barañao, José Lino S.
Calvo, Juan Carlos
Charreau, Eduardo Hernán
Effects of prolactin on androgen metabolism in androgen target tissues of immature rats
topic_facet androgen
androstane derivative
androstanolone c 14
bromocriptine
dopamine receptor
luteinizing hormone
prolactin
radioisotope
sulpiride
testosterone
testosterone c 14
unclassified drug
age
animal experiment
article
drug metabolism
endocrine system
male genital system
prostate
rat
seminal vesicle
testis
Androgens
Animals
Bromocriptine
Genitalia, Male
Male
Organ Size
Pimozide
Prolactin
Rats
Rats, Inbred Strains
Sexual Maturation
Sulpiride
Testis
Testosterone
description Testosterone metabolism in androgen target tissues of immature Wistar male rats was studied after the injection of ovine PRL (oPRL) or after changes in PRL levels induced by the administration of dopaminergic agonists or antagonists. Treatment with oPRL (500 μg/rat-day) for 10 days, starting on day 30 of age, caused a significant increase in testes and sex accessory organ weights and a concomitant augmentation in prostatic 5α-reductase activity. This effect, however, was not observed in epididymis and seminiferous tubules (ST). Daily administration of bromocriptine (3 mg/kg BW) using the same injection schedule suppressed endogenous PRL without altering serum LH levels. Testis and sex accessory organ weights and serum 5α-androstane-3α, 17β-diol levels were reduced in the animals treated with this dopaminergic agonist. These changes were associated with a significant decrease in 5α-reductase activity in both prostate gland and ST. Treatment with the dopaminergic antagonist sulpiride (43 mg/kg BW) during the same period induced a 4-fold increase in serum PRL levels, whereas LH levels remained unaltered. Although serum concentrations of testosterone (plus dihydrotestosterone) and 5α-androstane-3α, 17β-diol were significantly higher in sulpiride-treated rats, no significant changes in testis and sex accessory organ weights were detected in these animals. Sulpiride was unable to stimulate A4-5α-reductase activity in the prostate gland. Treatment with sulpiride or bromocriptine caused a significant increase in the 3α-hydroxysteroid dehydrogenase (3α-HDH) activity in ST. This effect was concomitantly seen in the ST and epididymides of 25-day-old rats after bromocriptine administration for 5 days. Another dopaminergic antagonist, pimozide, was also able to induce a similar increase in 3α-HDH activity in the ST and epididymis, even though chronic administration of this drug produced a significant decrease in serum PRL levels. The diminution in enzyme activity observed after the suppression of endogenous PRL levels by bromocriptine suggests that this hormone is involved in the control of Δ4-5α-reductase in the prostate and ST. However, induction of similar changes in the 3α-HDH activity by two dopaminergic agents with opposite effects on plasma PRL levels indicates the possibility of direct actions of these drugs on androgen target tissues. (Endocrinology 109: 2188, 1981). © 1981 by The Endocrine Society.
author Barañao, José Lino S.
Calvo, Juan Carlos
Charreau, Eduardo Hernán
author_facet Barañao, José Lino S.
Calvo, Juan Carlos
Charreau, Eduardo Hernán
author_sort Barañao, José Lino S.
title Effects of prolactin on androgen metabolism in androgen target tissues of immature rats
title_short Effects of prolactin on androgen metabolism in androgen target tissues of immature rats
title_full Effects of prolactin on androgen metabolism in androgen target tissues of immature rats
title_fullStr Effects of prolactin on androgen metabolism in androgen target tissues of immature rats
title_full_unstemmed Effects of prolactin on androgen metabolism in androgen target tissues of immature rats
title_sort effects of prolactin on androgen metabolism in androgen target tissues of immature rats
publishDate 1981
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00137227_v109_n6_p2188_Baranao
http://hdl.handle.net/20.500.12110/paper_00137227_v109_n6_p2188_Baranao
work_keys_str_mv AT baranaojoselinos effectsofprolactinonandrogenmetabolisminandrogentargettissuesofimmaturerats
AT calvojuancarlos effectsofprolactinonandrogenmetabolisminandrogentargettissuesofimmaturerats
AT charreaueduardohernan effectsofprolactinonandrogenmetabolisminandrogentargettissuesofimmaturerats
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