Accessory Organ Weights Research Articles

Active Principle of Swine Prostate Extract: II. Effect of a Peptide Isolated from Swine Prostate Extract on Rat Prostate

Previously, we purified a substance from swine prostate extract (PE) that had been reported to have therapeutic effect on benign prostatic hypertrophy. The purified substance (PPE) suppressed 3H-testosterone uptake into the prostate in castrated rats. The present study was carried out to examine the effect of PPE on the weight of accessory sexual organs including the prostate and biochemical parameters in the prostate of normal and/or castrated and testosterone-treated rats. 1) In normal rats, the p.o. administration of PPE daily for a total of 30 days did not affect the prostate weight, but reduced the citric acid content in the prostate. The treatment had little or no influence tissue O2 uptake, aconitase activity or isocitrate dehydrogenase activity in the prostate. 2) In castrated and testosterone-treated rats, the p.o. treatment with PPE for 15 or 30 days reduced the weight of the prostate as well as the total citric acid, DNA and RNA contents in prostatic tissue. However, these biochemical parameters per tissue weight were not obviously affected except for the citric acid content. These findings suggest that PPE is one of the active principals of PE for the therapeutic efficiency on benign prostatic hypertrophy, probably due to its suppressive effect on excessive uptake of androgen by the prostate.

Differential Effects of Follicle-Stimulating Hormone and Luteinizing Hormone on Leydig Cell Function and Restoration of Spermatogenesis in Hypophysectomized and Photoinhibited Djungarian Hamsters (Phodopus Sungorus)

Effects of pure human follicle-stimulating hormone (hFSH) and ovine luteinizing hormone (oLH) on testicular function were investigated in long-term hypophysectomized or photoinhibited Djungarian hamsters. hFSH (5 IU) or oLH (5 micrograms) or a combination of FSH and LH (5 IU and 5 micrograms, respectively) were injected s.c. twice daily for 7 days to hypophysectomized and photoinhibited hamsters. Other photoinhibited hamsters were treated for 14 and 21 days with FSH and LH (3 IU and 3 micrograms, respectively) in a similar way. LH alone had little, if any, effect on testicular weights; FSH, when injected alone or in combination with LH (FSH/LH), caused a significant increase in testes weights at each time point. On the other hand, LH or FSH/LH, but not FSH alone, caused a significant increase in the accessory organ weights. FSH had no effect on intratesticular testosterone (T) or on 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) activity but enhanced the in vitro response of interstitial cells to hCG. LH and FSH/LH had pronounced effects on intratesticular T, 3 beta-HSD activity, and in vitro response of interstitial cells to human chorionic gonadotropin. Treatment with FSH or FSH/LH caused regrowth of the testis and restoration of tubular lumen and tubular diameter and restored complete spermatogenesis. However, LH had little effect on spermatogenesis in spite of increased intratesticular and peripheral T levels. These results indicate that although LH can cause a full redifferentiation of Leydig cells in photoinhibited hamsters, it has only minor effects on tubular function. On the other hand, FSH alone induces full restoration of tubular function in these animals and has no direct effect on Leydig cell steroidogenesis, but may enhance the Leydig cell responsiveness to LH.

Altered gonadotropin and prolactin release induced by median eminence (ME) lesions and pharmacological manipulation of prolactin release: Further evidence for separate hypothalamic control of FSH and LH release

To delineate more clearly the regions of the median eminence involved in the control of gonadotropin secretion, electrolytic lesions were made in the median eminence of adult male rats. Also the role of prolactin in the maintenance of gonadotropin secretion and sex organs was further evaluated by the administration of α-bromo-ergocryptine (CB154) or its diluent SC to lower prolactin via its dopamine agonist action in these animals with lesions. The effects of elevation of prolactin by the administration in the drinking water of the dopamine antagonist, sulpiride, were also evaluated in intact rats. At the conclusion of the experiments the localization of lesions was carefully evaluated by microscopic examination of serial sections through the hypothalamic region. The results indicate that lesions which completely destroyed the median eminence led to elevation in plasma prolactin and profound decreases in plasma FSH and LH associated with atrophy of testes and accessory sex organs. This result was not affected if CB 154 was given to lower the elevated prolactin levels. Lesions which destroyed the rostral 2/3 of the median eminence were frequently associated with declines in plasma LH and relatively normal plasma FSH, whereas lesions which extended caudally to destroy the posterior median eminence were associated uniformly with a profound lowering of FSH. If these lesions did not include the anterior portions of the median eminence, LH levels remained normal. The results support the concept of separate control of FSH and LH release. LH release appears to be controlled particularly by the rostral 2 3 of the median eminence which is the presumed site of termination of the terminals of LHRH-secreting neurons, whereas FSH release is predominantly controlled by the posterior 2 3 of the median eminence, the presumed termination of the axons of the putative FSH-releasing factor neurons. The development of testicular atrophy and target gland atrophy was more closely associated with low plasma and pituitary FSH than LH which led to the suggestion that the release of FSH may be more important for maintenance of gonadal and target gland weight than that of LH. Elevation of plasma prolactin by administration of sulpiride failed to alter gonadotropin levels, testes weight or accessory organ weight. Since profound elevation or lowering of plasma prolactin did not alter the weights of testes or sex accessory organs, it appears that prolactin has little effect on these organs in adult in contrast to young rats.

Effect of pinealectomy on the undernutrition-induced suppression of the reproductive axis in rats.

Food restriction is known to sensitize the reproductive axis of rats to the inhibitory action of the pineal gland and its hormone, melatonin. The present study investigated the effect of pinealectomy on the undernutrition-related reproductive suppression. Three groups of animals (control, sham pinealectomy or pinealectomy) were subjected to either 3 weeks of 50% food restriction or ad libitum feeding under a lighting regimen of 14 h light and 10 h dark. At the end of the treatment period, body weight, testes weight, accessory organ weights, serum LH and serum testosterone were determined. In the pinealectomized animals, accessory organ weights and serum testosterone levels increased significantly. As compared to the controls, underfed pinealectomized animals had a partial recovery of the reduced accessory organ weights and normalization of the serum testosterone levels. These findings suggests that pinealectomy has a protective effect on the gonads of both control and underfed animals and that underfed animals are more sensitive to this protective mechanism.

Pituitary and Leydig cell function in boars actively immunized against gonadotrophin-releasing hormone.

Crossbred boars were (a) immunized against GnRH conjugated to human serum globulin (200 micrograms GnRH-hSG) in Freund's adjuvant at 12 weeks of age and boosted at weeks 18 and 20 (N = 10), (b) served as controls and received hSG only in adjuvant (N = 10), or castrated at weaning (N = 10). At 24 weeks of age (immediately before slaughter), the boars were challenged with saline or pig LH (1 microgram/10 kg body weight). After slaughter, fresh testicular fragments were incubated with pig LH (0.05 and 0.2 ng/2 ml medium) to assess the effects of immunization on Leydig cell function. Pituitary contents of LH and FSH, and testicular LH receptor content were also measured. The results indicated that plasma LH and testosterone concentrations, pituitary LH content, testicular LH receptor content, testis and sex accessory organ weights were significantly reduced in GnRH-immunized boars compared to hSG-adjuvant controls. However, plasma and pituitary FSH content were not affected by high antibody titres generated against GnRH. The testicular testosterone response to exogenous LH in vivo and in vitro was significantly reduced (P less than 0.05) in GnRH-immunized boars. These results indicate that active immunization against GnRH impairs pituitary and Leydig cell functions in boars.

Testicular involvement in peripubertal gonadotropin levels and accessory sex organ weight of male hamsters.

This study evaluates the influence of testicular secretions during development in male hamsters on peripubertal gonadotropin levels. Castration or sham operations were performed on the day of birth (Day 1), Day 5, 10, or 20 of life. Repeated plasma samples on Days 20-60 at 10-day intervals were taken via orbital sinus puncture. Castrated animals received a subcutaneous testosterone capsule on Day 60 and were killed on Day 70. In addition, seminal vesicles and ventral prostate weights were taken in all animals at Day 70. Castrated animals, regardless of day of castration, had higher gonadotropin levels and suppressed sexual accessory organ weights. Animals castrated on the day of birth had lower luteinizing hormone (LH) levels than animals castrated on other days. Castration on Day 10 resulted in lower follicle stimulating hormone (FSH) levels. Males castrated on Day 20 were most sensitive to the negative feedback effect of testosterone on LH secretion, while Day 10 castrates had elevated FSH levels after testosterone exposure. Sexual accessory weights also differed depending upon the day of castration. Results point out the importance of testicular secretions on the developmental processes as well as the differing ages at which various systems may be influenced.

A new non-hormonal antifertility drug DL-204: II. Effect on testicular hyaluronidase and gamma-glutamyl transpeptidase in male rats

Effects of DL-204, 2-(3-ethoxyphenyl)-5,6-dihydro (5,1-a)-isoquinoline, a non-hormonal antifertility drug on testicular hyaluronidase and gammaglutamyl transpeptidase levels, biochemical markers for testicular function, were evaluated in male rats. Treatment of 21-day-old rats with DL-204 for 7 or 15 days produced cryptorchid condition. Testicular hyaluronidase and gamma-glutamyl transpeptidase levels reveal that DL-204 acts on the testes, possibly in two ways; one, by reducing the gonadotropin levels thereby reducing the levels of androgens as reflected by reduced accessory reproductive organ weights and, secondly, by a direct action on the testes. Thus, we conclude that DL-204 is acting as an antispermatogenic agent, possibly acting in more than one way on the testes.

Methyl tertiary butyl ether inhalation in rats: a single generation reproduction study.

Male rats exposed to target concentrations of methyl tertiary butyl ether (MtBE) at 300, 1300 and 3400 ppm for 6 hours/day, 5 days/week for 12 weeks were mated to female rats exposed to the same concentrations for a 3-week period. Exposures continued through the mating period and the females continued exposures during gestation and from days 5-21 lactation of the litters (F1a) (no exposures days 0-4 lactation). A second litter (F1b) was produced under the same mating and post mating exposure regimen. No adverse effect of treatment was observed with the adult animals (Fo) throughout the in-life portion of the study. The only remarkable finding was an increased incidence of dilated renal pelves in the low- and high-dose females (Fo). All gonad weights, male accessory reproductive organ weights, organ-to-body weight ratios and reproductive organ histopathology were unremarkable upon comparison of treated animals with air sham controls. The mating indices and fertility indices in exposed animals for both mating intervals (F1a and F1b) were not significantly different from controls. Pregnancy rates were comparable between treated and control females for the first litter interval (F1a) but were slightly lower (not statistically significant) than control on the second litter interval (F1b). Treated animal mean gestation length and the mean number of pups at birth were not statistically different from controls. The pup viability indices at birth were comparable for control and treated groups for the F1a generation, but the mid- and high-dose groups displayed a slight statistically significant decrease in the F1b generation; the decrease was not considered to be biologically significant and perhaps not treatment-related. Litter survival indices were comparable between control and treated groups for both litter intervals. Pups of mid- and high-dose females had slightly lower (not statistically significant) mean weights at days 14 and 21 of lactation but this was not considered treatment-related. The most frequent post-mortem observation for pups sacrificed at day 21 of lactation was dilated renal pelves. This did not appear to be related to treatment. It is concluded that MtBE inhalation in rats results in little adverse reproductive toxicity as shown in a two litter, one generation reproduction assay in rats.

Effect of food restriction on 24-h serum and pineal melatonin content in male rats.

Food restriction (50%) effects on the 24-h rhythm of serum and pineal melatonin (MT) were studied in 260-300 g male Wistar rats under a lighting regimen of 14 h light and 10 h dark. Body weight, testicular weight, accessory organ weights, serum LH, serum testosterone, and 24-h rhythms of serum and pineal MT were determined. One week of food restriction caused a decrease in body weight (18%), accessory organ weights (18%), and serum LH (50%), but had no effect on serum or pineal MT. Three weeks of food restriction suppressed the body weight and accessory organ weights further (35% and 39%, respectively), reduced serum LH (68%) and serum testosterone (53%), reduced pineal MT (12%) and raised serum MT (34%). The increased serum MT may play a role in the reported potentiation of pineal action in food deprived rats.

Elevated ambient temperature retards the atrophic response of the neuroendocrine-reproductive axis of male Syrian hamsters to either daily afternoon melatonin injections or to short photoperiod exposure.

Adult male Syrian (golden) hamsters, maintained under either 22 +/- 2 or 32 +/- 2 degrees C, were treated with 8 or 11 weeks of exposure to either long photoperiod (14:10), short photoperiod (8:16), or to long photoperiod with a daily afternoon melatonin injection. By 8 weeks, the animals kept at 22 degrees C and treated with daily afternoon melatonin injection exhibited a dramatic reduction in testicular and accessory sex organ weight, but the animals kept at 32 degrees C and treated in the same way exhibited only slight decreases in testicular and accessory organ weights. Short photoperiod caused a slight decrease in testicular and accessory organ weights of hamster kept at 22 degrees C, while it had no significant effects on reproductive organ weights of the animals maintained under 32 degrees C. By 11 weeks, the daily afternoon melatonin injection elicited further reduction in testicular and accessory organ weights of the animals maintained under both 22 and 32 degrees C. However, the reduction in animals kept at 32 degrees C was not as great as that in animals kept at 22 degrees C. Although short photoperiod caused an obvious decline in reproductive organ weights of the animals at 22 degrees C, only a slight decrease was seen in hamsters at 32 degrees C. As with reproductive organ weights, testosterone levels were depressed more rapidly and completely in animals maintained at 22 degrees C. These results indicate that elevated ambient temperature changes the rate at which the gonads of hamsters regress in response to daily afternoon melatonin injections or short photoperiod.(ABSTRACT TRUNCATED AT 250 WORDS)

Reproductive effects of 6-chloromelatonin implants and/or injections in male and female Syrian hamsters (Mesocricetus auratus).

Adult female hamsters were injected each afternoon for 9 weeks with 2.5, 15 or 25 micrograms of melatonin or 6-chloromelatonin (CM). Each drug resulted in a significant dose-related depression in uterine, ovarian and anterior pituitary gland weights. Additionally, plasma and pituitary concentrations of prolactin fell with increasing dose of either indole whereas pituitary levels of LH and FSH were positively correlated with dose. There was no difference in effectiveness between the two drugs. Adult male hamsters treated for 10 weeks with daily afternoon injections of melatonin and a blank beeswax pellet had depressed testicular and accessory organ weights and plasma and pituitary concentrations of prolactin. Implantation of a 1 mg melatonin or CM beeswax pellet in hamsters concurrently receiving daily afternoon injections of melatonin prevented the organ weight and hormonal changes, except for plasma prolactin. Adult male hamsters treated for 10 weeks with daily afternoon injections of CM and a blank beeswax pellet had depressed reproductive organ weights and pituitary and plasma concentrations of prolactin; this depression in hormonal values and organ weights was totally prevented if the CM-injected hamsters were also bearing a beeswax-melatonin pellet. In conclusion, 6-chloromelatonin is as effective as melatonin with regards to antigonadotrophic and counter-antigonadotrophic effects in male and female Syrian hamsters.

Hormonal effects of ketoconazole in vivo in the male rat: mechanism of action.

Ketoconazole, an antifungal agent, has been shown to lower serum testosterone (T) in man. Measurements of circulating precursors of T suggest that ketoconazole may inhibit 17,20-desmolase activity in the testis. To further elucidate its mechanism of action in vivo, we studied its effects on the pituitary-gonadal axis in the male rate. Two groups of normal male Sprague-Dawley rats were treated with either oil or 25 mg ketoconazole in oil by im injection every 8 h for 21 days. Serum ketoconazole concentrations in the rat 2 h after the 25-mg dose were similar to those after oral administration of a much lower (1/33rd) dose to man. Ketoconazole treatment led to 50% suppression of serum T and prostate and seminal vesicle weights. Testis weights were not significantly affected. Intratesticular T concentrations showed a 50% decrease below the control level. Testicular 17 alpha-hydroxylase, 17,20-desmolase, and 17 beta-hydroxysteroid dehydrogenase activities in the ketoconazole-treated animals were significantly decreased in proportion to the decreases in serum and intratesticular T concentrations. Elevations of serum LH and FSH concentrations in the ketoconazole-treated rats were not proportionate to the decline in serum T concentration. Therefore, to exclude an additional inhibitory effect of ketoconazole at the pituitary level, we treated two groups of castrated male Sprague-Dawley rats with the same dose of ketoconazole or oil for 3 days. Serum LH and FSH concentrations were not significantly different in the two groups. In separate experiments, combined treatment of intact rats with GnRH agonist and ketoconazole for 21 days led to lower mean serum T concentrations and accessory organ weights than those achieved with either agent alone. We conclude that ketoconazole inhibits T synthesis, primarily by inhibiting the activity of multiple enzymes in the T biosynthetic pathway and has no direct effect at the pituitary level; ketoconazole metabolism in the rat is considerably different from that in man; and ketoconazole enhances the inhibitory effects of GnRH agonist.

Imprinting of male sex tissues by neonatal endogenous androgens in mice. Molecular alterations following exposure to cyproterone acetate.

This study was conducted to evaluate the growth and biochemical responsiveness of the epididymis, vas deferens and seminal vesicles of adult mice exposed to cyproterone acetate during the first 10 days of life. Results indicate that the weight and protein content of sex accessory organs were significantly depressed, testosterone and dihydrotestosterone concentrations were unaffected or increased, the number of cytosolic androgen-binding sites was slightly or significantly reduced. The efficiency of exogenous testosterone in promoting growth and protein synthesis in target organs of castrated adult males was significantly lowered by neonatal cyproterone acetate treatment. It is concluded that a deficient androgenic stimulation during neonatal life induces a limited response of sex target organs to endogenous or exogenous androgens in adulthood.

A new non-hormonal antifertility drug DL 111-IT: I. Effects on testes and accessory glands of reproduction in male rats

Effect of DL-111, 3-(2-ethylphenyl)-5-(3-methoxyphenyl-1H-1,2,4-triazole, a non-hormonal postimplantational antifertility agent, on testicular and accessory reproductive organ weights and total protein, RNA and DNA concentrations were evaluated in immature and adult rats. Treatment of 21-day-old rats at doses of 2.5 mg and 5 mg/kg body weight decreased body weight, weights of testes and accessory glands of reproduction. RNA and protein concentrations decreased significantly with significant increase increase in DNA concentration in testes, epididymis, ventral prostate and seminal vesicles. DL-111 treatment of adult rats at doses of 5 mg and 10 mg/kg body weight had no effect on body weight, but significantly decreased weights of testes and accessory glands of reproduction. RNA and protein concentrations decreased significantly in all tissues studied while DNA concentration was not altered. RNA/DNA ratio decreased significantly, reflecting ribosomal loss and cytoplasmic shrinkage. These effects of DL-111 are comparable to post-castrational changes in accessory glands of reproduction. We presume that these changes are mediated by blocking the androgen biosynthesis and/or by interfering with normal function of hypothalamo-pituitary-gonadal axis.

Diurnal sensitivity of the neuroendocrine-reproductive axis to the antigonadotrophic influence of melatonin in male Syrian hamsters with experimentally altered cortisol rhythms.

Two different experimental models were used to test if a temporal relationship exists between the rhythm of adrenal steroid secretion and the vulnerability of the hamster reproductive system to short photoperiod exposure or to the daily afternoon injection of melatonin. In the first experiment adrenalectomized hamsters were implanted with a cortisol pellet to provide a sustained, rather than rhythmic, level of the hormone. The animals were either placed in short photoperiod or given a daily afternoon melatonin injection. In both cases the gonads underwent atrophy. In the second experiment adrenalectomized hamsters were given a cortisol injection either in the morning (approx. 8 hr before the subsequent afternoon injection of melatonin) or in the afternoon (approx. 1 hr before the subsequent melatonin injection). Measurements of testicular and accessory organ weights 7 weeks later indicated regression of the reproductive system in both the groups when compared with their appropriate controls. Depressed levels of plasma LH, PRL, testosterone and thyroxine (T4) in these animals confirmed the melatonin induced gonadal collapse. The results suggest that apparently there is no temporal correlation between the rhythm of secretion of the adrenal steroids and the responsiveness of the reproductive system to late afternoon injection of melatonin. Interestingly, all the adrenalectomized cortisol injected control animals (not receiving melatonin) had depressed plasma LH and PRL while the testicular weights and plasma testosterone titers remain unaffected.

Altered responses to androgen in diabetic male rats.

In male rats, experimentally induced diabetes mellitus has been reported to be associated with reduced serum levels of gonadotropins and testosterone as well as decreased sex accessory organ weights. The purpose of the present study was to determine if the decreased accessory organ weights and gonadotropin levels observed in diabetic animals result from alterations in the ability of target tissues to respond to testosterone. Adult, male, Wistar rats were injected with streptozotocin (STZ) and either maintained as untreated diabetics or treated with daily injections of insulin. Semi-starved animals were included to control for any effects on the reproductive system due to body weight change alone. These three groups, plus intact controls, were maintained for 30 days with one-half of the animals from each group receiving silastic tubing implants of testosterone of various lengths. It was determined that, in uncontrolled diabetic and semi-starved animals, the serum levels of LH, FSH, and testosterone were decreased, as were the weights of seminal vesicles and ventral prostate glands. Insulin treatment restored LH, FSH, and testosterone levels to normal. Sex accessory glands exhibited slight, but significant, recovery in diabetic animals treated with insulin. Implants of testosterone that resulted in physiologic serum levels of testosterone were effective in depressing serum LH and FSH levels as well as in maintaining normal seminal vesicle and ventral prostate weights in control and semi-starved animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Contribution of self-grooming to onset of puberty in male rats.

Self-grooming was observed to increase during the prepubertal period of Long-Evans rats. Males were significantly more likely than females to engage in genital grooming during this period. To determine whether self-grooming contributes to the onset of puberty, males were fitted with collars that either prevented or allowed self-grooming of hindquarters or were left uncollared from 27 to 48 or 55 days of age when autopsied to determine weight of accessory organs. Ventral, dorsal, and lateral prostates and seminal vesicles were significantly lighter in those rats wearing collars that prevented self-grooming. It was concluded that self-grooming, probably of the genitals, contributes to accessory organ growth in males of this species.

In vivo patterns of circulating testosterone following castration and intramuscular testosterone propionate injections of adult male rats

In vivo patterns of circulating testosterone (T) were investigated in castrated and in intact male rats following a single intramuscular injection of 1mg testosterone propionate (TP). In addition, the in vivo clearance pattern of T was investigated following castration. The injection of TP into intact rats resulted in a rapid, statistically significant increase in circulating T which lasted for 12h and returned to normal by 24h post-injection. Circulating T decreased to nondetectable levels by 6h following orchiectomy. Injection of TP into castrated rats caused a rapid increase in circulating T which reached highest levels 60 min after administration. The concentrations of T in TP-treated orchiectomized rats remained elevated for 12h with a gradual decline which persisted for the experimental period of 6 days post-injection and provided moderate maintenance of sex accessory organ weights. TP injections increased circulating T levels in both groups of rats, but the magnitude of elevation was greater in intact animals where the normal T diurnal variations were disturbed. The elevation in circulating T persisted longer in the castrate-TP-treated animals than in intact animals, suggesting a difference in clearance, distribution and metabolism of T in orchiectomized rats.

Effect of chronic administration of inhibin and testosterone on spermatogenesis in adult male rats.

Inhibin (Inh) and testosterone (T) were administered to adult male rats for 32 days to evaluate their effect on spermatogenesis. Fifty micrograms of Inh was injected subcutaneously twice daily, and T was administered as Silastic implants 2.5 cm in length. Weights of testes and epididymides were significantly decreased in (Inh + T)- and T-treated groups, but not in Inh-treated rats. Although Inh alone could suppress both the testicular and the epididymal sperm count, maximum suppression was observed in the (Inh + T)-treated group. The effect on the epididymal sperm count, however, was pronounced. The accessory organ weights remained unaffected in all treated groups. Chronic administration of Inh and T results in partial impairment of spermatogenesis.

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 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...