Inhibitory Effect Of Androgens Research Articles

Inhibitory effect of androgens on white adipose tissue thermogenic capacity

White adipose tissue (WAT) browning has gained interest due to its impact in obesity. Here, we evaluated the effect of androgens on the Ucp1-dependent thermogenic process from inguinal (IAT) and retroperitoneal (RPAT) WAT. Surgically androgens depleted rats (ODX) showed basal thermogenic activation (room temperature) in both WAT depots, which expressed higher levels of Ucp1, Prdm16 and Pgc1a. WAT pads from ODX cold-exposed rats (ODX-C) expressed increased levels of Ucp1 and Pgc1a and showed high UCP1 protein content. In primary beige adipocyte cultures, testosterone decreased the mitochondrial marker Cox8b and mitochondrial content. Finally, testosterone and dihydrotestosterone (DHT) decreased the expression of Ucp1, Pcg1a and Prdm16 in forskolin-stimulated beige adipocytes, an effect that was prevented by the antiandrogen flutamide. In conclusion, androgen deficient rats developed WAT depots with enhanced basal and cold-stimulated thermogenic activity. Additionally, in vitro androgen treatments inhibited the thermogenic program, effect which was mediated by the androgen receptor pathway.

Gynecomastia in Infants, Children, and Adolescents.

Gynecomastia may occur physiologically in the neonatal period, during puberty, and in old age. It may also develop in association with various pathologic states. The challenge for the physician is to distinguish physiological gynecomastia from those with an underlying pathology. To review in depth the pathophysiology, clinical manifestations, and treatment of gynecomastia. A PubMed search was completed in Clinical Queries using the key term "gynecomastia". Patents were searched using the key term "gynecomastia" from www.google.com/patents, www.uspto.gov, and www.freepatentsonline.com. Gynecomastia is caused by an imbalance between the stimulatory effect of estrogen and the inhibitory effect of androgen at the breast tissue level. Clinically, gynecomastia is characterized by the presence of a firm or rubbery, discrete, subareolar ridge of glandular tissue that is symmetrical in shape, freely movable, and nonadherent to skin or underlying tissue. Since most cases of physiological gynecomastia regress spontaneously with time, reassurance is all that is necessary. For pathological gynecomastia, treatment should be directed at the underlying cause, if possible. If gynecomastia persists in spite of the above measures, pharmacologic therapy and reduction mammoplasty may be considered. Recent patents related to the management of gynecomastia are discussed. The majority of cases are physiological and do not require treatment other than reassurance. For pathological cases, the underlying cause should be treated if possible. If gynecomastia persists in spite of the above measures and treatment becomes necessary, tamoxifen is the treatment of choice. Reduction mammoplasty may be considered for resistant cases.

A clinical approach to gynecomastia

Gynecomastia is the commonest breast condition in male, which can cause significant psychological distress and anxiety to the patient. It refers to the benign enlargement of the male breast caused by proliferation of glandular breast tissue due to an imbalance between the inhibitory effect of androgen and stimulatory effect of estrogen. Gynecomastia can be physiological during neonatal period, puberty or old age. Various drugs, systemic disorders, benign or malignant tumours and hypogonadism can also lead to gynecomastia, while about 25% of cases are idiopathic. Gynecomastia should be differentiated from pseudogynecomastia (adipomastia), which is characterized by excessive accumulation of adipose tissue without glandular proliferation. A detailed history and examination helps to exclude differential diagnosis, identify the underlying etiology and to assess the severity of the disease and the concerns of the patient. The management of gynecomastia depends on the underlying etiology and the concerns of the patient. This may include interventions for relief of pain or discomfort, restoration of normal appearance and reassurance regarding cancer. Treatment options include watchful waiting, pharmacotherapy and surgery. Sri Lanka Journal of Diabetes, Endocrinology and Metabolism 2015; 5: 23-27

Abstract P6-04-17: The androgen metabolite-dependent growth in hormone receptor positive breast cancer as a novel aromatase inhibitor-resistance mechanism

Abstract Introduction: Aromatase inhibitors (AIs) have been reported to exert their anti-proliferative effects not only by reducing the production of estrogens but also by unmasking the inhibitory effect of androgens such as testosterone (TS) or dihydrotestosterone (DHT) in postmenopausal women with hormone receptor-positive breast cancer. The behavior of androgens in AI-resistance mechanisms is not sufficiently understood. 5α-androstane-3β,17β-diol (3β-diol) generated from DHT by 3β-hydroxysteroid dehydrogenase type 1 (3β-HSD type 1: HSD3B1) has androgenic activity and substantial estrogenic activity, representing a potential mechanism of AI resistance. Methods: To investigate these issues, ERE-GFP-transfected MCF-7-E10 cells were cultured for 3 months under steroid-depleted, TS-supplemented conditions which is the similar as the AI treatment. Among the surviving cells, two stable variants that show ER activity depending on androgen metabolites were selected as AD-EDR (androgen metabolite-dependent and estrogen depletion-resistant) by monitoring GFP expression. Using these cell lines, we investigated the process of adaptation to androgen-abundant conditions and the role of androgens in AI-resistance mechanisms. Results: AD-EDR cell lines showed increased growth and induction of estrogen-responsive genes rather than androgen-responsive genes by androgens or 3β-diol. Further analysis revealed increased expressions of HSD3B1 and reduced expression of androgen receptor (AR) in these cell lines. In parental MCF-7-E10 cells, ectopic expression of HSD3B1 or inhibition of AR resulted in adaptation to estrogen-deprived and androgen-abundant conditions. In coculture with stromal cells replicating the local estrogen production from androgen, AD-EDR cell lines showed AI resistance compared with parental MCF-7-E10 cells. Immunohistochemistry and real-time PCR analyses on 9 pairs of primary and recurrent tissue samples from AI-resistant breast cancer revealed the decrease of AR protein expression in all cases and increase of HSD3B1 mRNA expression in 5. Conclusion: In the present study, we successfully cloned two stable variants that show ER activity depending on androgen metabolites. Investigation of these cell lines suggested that the increased function of 3β-HSD type 1 and reduced function of AR contribute to AI resistance by enhancing the androgen metabolite-dependent growth and reducing the inhibitory effect of androgens. Our data of clinical samples suggest that this mechanism also acts as an AI-resistance in clinical breast cancer in some cases. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-04-17.

Unilateral Gynecomastia in a Tennis Player

Unilateral Gynecomastia in a Tennis Player

Organizational role for pubertal androgens on adult hypothalamic‐pituitary‐adrenal sensitivity to testosterone in the male rat

The inhibitory effect of androgens on the hypothalamic-pituitary-adrenal (HPA) axis in basal and stress conditions in adult male rats is well documented. Major sex-related neuroendocrine changes take place during puberty. There is a robust rise in production and secretion of gonadal steroids, which is thought to underlie numerous neural and behavioural changes brought on after puberty. The present study investigated the effect of the pubertal rise in gonadal steroid levels on the subsequent adult corticosterone profile, particularly the sensitivity of the adult HPA axis to testosterone. Animals were castrated either prepubertally (28 days) or in adulthood (11 weeks) and adult animals were subsequently treated with subcutaneous implants containing either testosterone or cholesterol. Using an automated blood sampling system, blood was collected from each freely moving, conscious rat every 10 min (i) over a 24 h period; (ii) in response to 10 min of noise stress, and (iii) following an immunological challenge with lipopolysaccharide (LPS). Analysis revealed that testosterone treatment did not significantly affect overall corticosterone release over the 24 h period in adult animals castrated before puberty in contrast to animals castrated in adulthood in which testosterone significantly suppressed corticosterone secretion. Following either a noise stress or LPS injection, testosterone treatment did not affect the hypothalamic or adrenal stress response in animals castrated prepubertally. Testosterone significantly suppressed the corticotrophin-releasing hormone and arginine vasopressin mRNA as well as the corticosterone response to LPS in castrated animals that had had their testes intact over puberty. These data provide evidence that puberty is a critical organizational period during which rising levels of gonadal steroids programme the sensitivity of the adult HPA axis to gonadal steroids in adulthood.

Testosterone Inhibits Adipogenic Differentiation in 3T3-L1 Cells: Nuclear Translocation of Androgen Receptor Complex with β-Catenin and T-Cell Factor 4 May Bypass Canonical Wnt Signaling to Down-Regulate Adipogenic Transcription Factors

Testosterone supplementation in men decreases fat mass; however, the mechanisms by which it inhibits fat mass are unknown. We hypothesized that testosterone inhibits adipogenic differentiation of preadipocytes by activation of androgen receptor (AR)/beta-catenin interaction and subsequent translocation of this complex to the nucleus thereby bypassing canonical Wnt signaling. We tested this hypothesis in 3T3-L1 cells that differentiate to form fat cells in adipogenic medium. We found that these cells express AR and that testosterone and dihydrotestosterone dose-dependently inhibited adipogenic differentiation as analyzed by Oil Red O staining and down-regulation of CCAAT/enhancer binding protein-alpha and -delta and peroxisome proliferator-activated receptor-gamma2 protein and mRNA. These inhibitory effects of androgens were partially blocked by flutamide or bicalutamide. Androgen treatment was associated with nuclear translocation of beta-catenin and AR. Immunoprecipitation studies demonstrated association of beta-catenin with AR and T-cell factor 4 (TCF4) in the presence of androgens. Transfection of TCF4 cDNA inhibited adipogenic differentiation, whereas a dominant negative TCF4 cDNA construct induced adipogenesis and blocked testosterone's inhibitory effects. Our gene array analysis indicates that testosterone treatment led to activation of some Wnt target genes. Expression of constitutively activated AR fused with VP-16 did not inhibit the expression of CCAAT/enhancer binding protein-alpha in the absence of androgens. Testosterone and dihydrotestosterone inhibit adipocyte differentiation in vitro through an AR-mediated nuclear translocation of beta-catenin and activation of downstream Wnt signaling. These data provide evidence for a regulatory role for androgens in inhibiting adipogenic differentiation and a mechanistic explanation consistent with the observed reduction in fat mass in men treated with androgens.

The inhibitory effect of androgen and sex-hormone-binding globulin on the intracellular cAMP level and tyrosinase activity of normal human melanocytes.

The effect of androgens on human melanocytes has not been well clarified. We studied the effects of androgens on normal human melanocytes in the presence or absence of sex-hormone-binding globulin (SHBG), which complexes with those hormones. Immunohistochemically, testosterone and SHBG co-localized on the cell membrane. Androgens such as testosterone, 5alpha-dihydrotestosterone, and methyltrienolone (R1881, a potent synthetic androgen), reduced intracellular cAMP levels after treatment with SHBG, but hydrocortisone had no effect. We also found that testosterone and R1881 slightly suppressed tyrosinase activity in melanocytes when treated with SHBG, although they had no effect on the expression of tyrosinase at the transcriptional or translational level, as measured by semi-quantitative reverse transcriptase-polymerase chain reaction and by Western blot analysis, respectively. Our results suggest that androgens may modulate tyrosinase activity at the posttranslational level through the cell membrane signaling pathway.

Glucoprivation counteracts effects of testosterone on daily torpor in Siberian hamsters.

We tested whether 1) glucose availability is a signal for initiation of torpor in male hamsters and 2) glucoprivation can override the inhibitory effects of androgens on daily torpor. Male hamsters maintained at ambient temperatures of 8-16 degrees C were injected with 2-deoxy-D-glucose (2DG), a glucose analogue that interferes with cellular glucose oxidation. 2DG (2,000-2,500 mg/kg body mass) induced torpor within 1 h of treatment in normal adult males in reproductive condition and in those bearing testosterone (T)-filled capsules that produced supraphysiological blood T concentrations; body temperatures were reduced from 37 to 25 degrees C for several hours. Latency to torpor was increased and duration of torpor was decreased in the T-treated hamsters. Food intake decreased substantially both on the day of torpor and on the succeeding day. Glucoprivation appears to counteract the potent inhibitory effect of androgens on torpor and induces a hypometabolic state that results in overall energy savings.

Regulation of Prolactin Messenger Ribonucleic Acid Levels by Estradiol and Dihydrotestosterone as Evaluated by in situ Hybridization Performed on Implanted Pituitary Glands and Anterior Pituitary Cells in Culture in the Male Rat

We have recently demonstrated that 17ß-estradiol (E(2) ) administration increases protactin (PRL) mRNA levels in the male rat anterior pituitary gland and that this stimulatory effect is partially inhibited by concomitant administration of dihydrotestosterone. In order to gain more information about the site(s) of action of E(2) and dihydrotestosterone on PRL gene expression, we have studied the effects of these two hormones in pituitaries implanted under the kidney capsule as well as in anterior pituitary cells in culture. In implanted pituitaries, PRL mRNA levels were increased by 90% as compared to values obtained in the stalk-connected pituitaries from the same animals. Administration of E(2) induced a further increase of PRL mRNA levels in implanted pituitaries, while dihydrotestosterone did not produce any change in animals which had been treated or not with E(2) . In anterior pituitary cells in culture, addition of E(2) to the culture medium resulted in a 60% increase of PRL mRNA levels over control values. Supplementation with dihydrotestosterone did not induce any variation in the concentration of PRL mRNA in cells which were treated or not with E(2) . These results indicate that E(2) exerts a direct action on PRL cells at the pituitary level and strongly support the key role of the hypothalamus in the inhibitory effect of androgens on estrogen-induced stimulation of PRL mRNA in the male rat pituitary.

Inhibitory effect of androgen on cell death of mouse uterine epithelium

The protective effect of androgen against the cell death of mouse uterine epithelium was evaluated by examining the retention of 5'-[ 125I]iodo-2'-deoxyuridine ([ 125I]IdUrd) incorporated into the whole uterus and the apoptotic index (percentage of the apoptotic cells to the total cells) which is a good index of physiological cell death. Castrated adult female mice were daily injected with oestradiol-17β for 3 days, followed by the injection of [ 125I]IdUrd. Thereafter, these mice were daily injected with only the vehicle or 5α-dihydrotestosterone (DHT), and the 125I-radioactivity retained in the whole uterus was determined. When only the vehicle was injected, the 125I-radioactivity retained in the whole uterus rapidly decreased but injections of DHT reduced the loss of 125I-radioactivity. The effect of DHT on the retention of 125I-radioactivity depended on doses of DHT and was abolished by the pure antiandrogen, flutamide. The apoptotic index of uterine cells was examined by a similar experimental protocol, but without an injection of [ 125I]IdUrd. Injections of only the vehicle caused marked increases in the apoptotic indices of both luminal and glandular epithelia, but injections of DHT decreased them significantly. The apoptotic index of stroma was not affected by the injection of DHT. The present results indicate that androgen reduces the cell death of mouse uterine epithelium through the androgen receptor.

Inhibitory effect of androgens on DMBA-induced mammary carcinoma in the rat

Constant release of the androgen 5 alpha-dihydrotestosterone (DHT) in ovariectomized rats bearing DMBA-induced mammary carcinoma caused a marked inhibition of tumor growth induced by 17 beta-estradiol (E2). That DHT acts through interaction with the androgen receptor is supported by the finding that simultaneous treatment with the antiandrogen Flutamide completely prevents DHT action. Particularly illustrative of the potent inhibitory effect of DHT on tumor growth are the decrease by DHT of the number of progressing tumors from 69.2% to 29.2% in E2-treated animals and the increase by DHT of the number of complete responses (disappearance of palpable tumors) from 11.5% to 33.3% in the same groups of animals. The number of new tumors appearing during the 28-day observation period in E2-treated animals decreased from 1.5 +/- 0.3 to 0.7 +/- 0.2 per rat during treatment with DHT, an effect which was also reversed by the antiandrogen Flutamide. The present data demonstrate, for the first time, that androgens are potent inhibitors of DMBA-induced mammary carcinoma growth by an action independent of inhibition of gonadotropin secretion, and suggest an action exerted directly at the tumor level.

Inhibitory effect of androgen on estrogen-induced prolactin messenger ribonucleic acid accumulation in the male rat anterior pituitary gland.

Estrogens are known to exert specific stimulatory effects on basal and dopamine-inhibited PRL secretion and synthesis as well as on PRL gene expression. However, dihydrotestosterone (DHT) and progesterone (P), although inactive alone, can reverse the effect of 17 beta-estradiol (E2) on PRL release both in vivo and in vitro. Using castrated male rats, we have studied the effect of E2 (0.25 micrograms), P (2 mg), or DHT (100 micrograms) administered twice daily for 14 days alone or in combination on pituitary PRL mRNA levels measured by quantitative in situ hybridization. Treatment with E2 increased the accumulation of PRL mRNA by about 2.6-fold. Administration of P or DHT alone failed to modify PRL mRNA concentrations. However, DHT could prevent by 80% the stimulatory effect of E2 on PRL mRNA levels. Similar results were obtained by dot blot hybridization assay. The effects of sex steroids on PRL mRNA were closely paralleled to pituitary PRL content measured by RIA. The present data demonstrate that the effect of sex steroids on immunodetectable PRL result from a modulation of PRL mRNA accumulation. The sexual dimorphism observed in pituitary PRL content results from a 3.5-fold greater accumulation of PRL mRNA in intact females than in male rats. These results also clearly show that quantitative in situ hybridization is a powerful tool in the investigation of the regulation of gene expression in addition to providing valuable information on the localization of specific mRNA.

Testicular Peritubular Cells Secrete a Protein under Androgen Control that Inhibits Induction of Aromatase Activity in Sertoli Cells*

We investigated the role of peritubular cell-Sertoli cell interactions in the control of Sertoli cell function by androgens. Decreased FSH-inducible aromatase activity and increased secretion of androgen-binding protein (ABP) were used as parameters of androgen action on Sertoli cells. It is demonstrated that coculturing Sertoli cells with limited amounts of peritubular cells (20%) has only marginal effects on inducible aromatase activity or ABP secretion, but markedly increases the response of these parameters to androgens. Conditioned media derived from peritubular cells pretreated with androgens mimick the effects observed in the coculture system. Evidence is presented that androgen action on peritubular cells is mediated by an androgen receptor and that the concentration of this receptor is increased up to 3-fold by androgens. Preliminary experiments suggest some analogy between the peritubular cell factors that stimulate ABP production and those that inhibit aromatase induction. The active principles responsible for both activities are thermolabile trypsine-sensitive proteins with a mol wt between 50,000-100,000, and androgen induction by both activities shows an identical time course, characterized by a 4-day latent period. Nonetheless, much higher concentrations of peritubular cell secretion products seem to be required to inhibit aromatase induction than to stimulate ABP production, indicating that the active principles are not necessarily identical. It is concluded that peritubular cell secretion products mimick and mediate not only stimulatory but also inhibitory effects of androgens on Sertoli cells.

The endogenous concentration and subcellular distribution of androgens in normal human premenopausal endometrium, myometrium and vagina.

The endogenous concentrations of testosterone (Testo), androstenedione (Adion), 5-androstene-3 beta, 17 beta-diol (Adiol), dehydroepiandrosterone (DHEA) and DHEA-sulfate (DHEAS) have been measured in endometrium, myometrium and vagina from 23 premenopausal women at different stages of the cycle. The tissue to plasma gradient was positive for all androgens except DHEAS; a significant correlation existed between plasma and tissue levels of Adiol and DHEAS. In all tissues significant correlations were calculated between Adiol and DHEA, Adion and Testo, and Adiol and DHEAS. Except for Testo, androgen concentrations were different in the tissues with a significant correlation between the tissues, each tissue seeming to be able to create its own specific intratissue androgen pattern. During the cycle Testo was highest in myometrium and vagina and Adion in myometrium and endometrium during the secretory phase. Except for DHEA, androgens were preferentially localized in the cytosol fraction of the cells. From this localization and the known inhibitory effects of androgens on the activity of estrogen metabolizing enzymes, it is postulated that androgens play a role in enzymatic rather than receptor-mediated processes in uterine cells.

Inhibitory effect of androgen on the synthesis of proteinase F in the male mouse submandibular gland.

Androgenic regulation of one of the esteroproteinases (proteinase F) in the mouse submandibular gland was studied using specific antiserum. In contrast to esteroproteinases such as proteinases A, D or P-esterase, proteinase F content in male but not in female mice was increased by gonadectomy and decreased by the injection of various androgens. In-vivo incorporation of [3H]leucine into proteinase F in males was increased after castration and decreased by the injection of testosterone propionate; androgens inhibited the de-novo synthesis of proteinase F in male mice. The dose-response curves for testosterone propionate and time-courses following castration or after the injection of testosterone propionate were reciprocal between proteinase F and total esteroproteinase activity. Proteinase F, like other esteroproteinases in the submandibular gland of the mouse, was localized in granular convoluted tubular cells. These data indicate that granular convoluted tubular cells of the male mouse submandibular gland synthesize both androgen-inducible proteinases and androgen-inhibitory proteinase (proteinase F).

Therapeutic studies in New Zealand mice. VII. Successful androgen treatment of NZB/NZW F1 females of different ages.

AbstractIn view of the known inhibitory effects of androgens on the spontaneous production of autoantibodies in hybrids of NZB mice, as well as the dramatic effects of sex hormones on the modulation of autoimmunity in NZB/NZW F1 mice, we undertook a systematic study of treatment of female NZB/NZW mice with androgens. We initiated treatment at 0.5, 3, 5, 6, 7, or 8 months of life in castrated or intact mice by use of one of three steroid preparations at different doses. We found that danazol was not effective in suppressing proteinuria, reducing antibodies to ssDNA, or in prolonging survival. In contrast, both testosterone and 5 α‐dihydrotestosterone were capable of prolonging survival, suppressing proteinuria, and reducing anti‐ssDNA in both intact and castrated mice. Testosterone was effective at lower doses than was the 5 α hormone. Testosterone significantly prolonged survival even when started after the onset of clinical illness at 5, 7, and 8 months of age. Mice treated from 5 months of life with testosterone had a much more marked reduction in antibodies to ssDNA than to native DNA. However, treatment from 7 months of age significantly prolonged survival without altering the serum levels of either autoantibody, suggesting that some other mechanism of testosterone action may be contributing to therapeutic efficacy. These studies indicate that androgen therapy may be beneficial even after the development of clinical illness, that castration is not necessary for benefit, and that the effectiveness of a therapeutic regimen is dependent upon both the dose and the particular preparation of hormone.

BINDING OF HUMAN GROWTH HORMONE TO HEPATIC LACTOGENIC BINDING SITES: REGULATION BY OESTROGENS AND ANDROGENS

The binding of 125I-labelled human growth hormone (HGH) to the 'lactogenic' binding sites of rat liver membranes has been shown to be highly dependent on the oestrogen and androgen status of the membranes has been shown to be highly dependent on the oestrogen and androgen status of the animal from which the membranes were prepared. Oestradiol treatment of either male or female rats induced a highly significant rise in HGH binding. The minimum effective dose used was 2-5 mug/day and the rise in HGH binding was apparent after 4 days of treatment. Folowing cessation of oestradiol treatment of male rats HGH binding declined with a half-time of approximately 9 days. In contrast to the stimulatory effect of oestrogen, treatment of female rats with testosterone propionate (minimum effective dose 100-200 mug/day) led to a marked reduction in HGH binding. The influence of both oestrogens and androgens was confirmed following the removal of endogenous sex steroids by adrenalectomy-ovariectomy of female rats and castration of male rats. Scratchard analysis showed that, with the possible exception of adrenalectomy-ovariectomy, all pharmacologically and physiologically induced changes in HGH specific binding reflected changes in binding site capacity; there were no changes in binding affinity. While earlier studies have indicated that the oestrogen effect is primarily indirect and is mediated by the pituitary gland, the mode of action of the androgens is currently unknown. The relatively slow response of HGH binding to hormonal changes would support an indirect action for both the sex steroids. The stimulatory effect of oestrogens and the inhibitory effect of androgens may provide an explanation for the marked sex difference in HGH binding to rat liver membranes.

Effects of gonadectomy and replacement therapy on adrenal function in the domestic duck, Anas platyrhynchos

Adrenal function in ducks of both sexes was studied in intact and in castrated animals and in castrated animals receiving appropriate replacement therapy. No significant changes in adrenal weights were observed in the various groups of animals. In the males, in vitro production of corticosteroids from progesterone-4- 14C by both the intact and castrated animals receiving testosterone phenylpropionate were significantly less than by the castrates, indicating an inhibitory effect of androgens on adrenal activity. No differences were observed in the three groups of female ducks.

Inhibitory effect of androgen on induction of permanent changes in the testis by neonatal injections of estrogen in mice.

In male mice which had been given 15 daily injections of estradiol-17β(E) from the day of birth, 20μg for the first 10 days and 40μg for the following 5 days, spermatogenesis was permanently inhibited. Both the seminiferous epithelium and the interstitial tissue of the testes were highly deranged in half the number of the animals at 60 days of age. If testosterone propionate (TP), 4-40μg for the first 10 days and 8-80μg for the following 5 days, was injected simultaneously with E, active spermatogenesis was going on in the testes when examined at 60 days, although the testes were smaller than those in the oil controls. The epithelium of the seminal vesicles and ventral prostates was stimulated by endogenous androgen in the mice given E plus TP.