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PubMed1998

Hirsutes. II: Treatment.

The treatment of hirsutes includes cosmetic measures, such as bleaching, plucking, electrical epilation and, more recently, laser epilation. Pharmacological therapy consists of anti-androgens and includes the androgen receptor blockers spironolactone and cyproterone acetate. Other drugs reducing androgen expression include oral contraceptives and corticosteroids. A new follicular 5 alpha reductase inhibitor, finasteride, is currently under evaluation, as is the anti-androgen flutamide. Gonadotrophin-releasing hormone agonists reduce androgen expression and show early promise in the treatment of hirsutes.

5-alpha Reductase Inhibitors↗
PubMed2005

Frontal fibrosing alopecia: a survey in 16 patients.

BACKGROUND: Postmenopausal frontal fibrosing alopecia (PFFA) was described by Kossard et al. as a progressive recession of the frontal hairline affecting particularly postmenopausal women. Further cases of PFFA have been reported to date, all of them considering it as a variant of lichen planopilaris on the basis of its clinical, histological and immunohistochemical features. OBJECTIVE: To describe clinical features, and response to treatment of 16 cases of frontal fibrosing alopecia diagnosed at our department in the last 6 years. METHODS: In addition to clinical data, biopsies and laboratory tests (antinuclear antibodies, sex hormones, thyroid hormones) were performed in order to rule out other causes of scarring alopecia. Patients were treated with intralesional corticosteroids, finasteride, and minoxidil, depending on the stage of the disease and association to androgenetic alopecia. RESULTS: All patients presented progressive alopecia localized to the frontal and temporal hairlines. Eight patients (50%) had loss of eyebrows, and six patients (37.5%) had axillar alopecia. Ages ranged from 45 to 79. Three of these women were premenopausal. Androgenetic alopecia was evident in seven patients (43.8%). All patients biopsied showed perifollicular lymphocitic infiltrate with lamelar fibrosis limited to the upper portions of the follicle. The progression of the condition stopped in most patients after a variable period on treatment. When treatment was abandoned the alopecia progressed to 'clown alopecia' appearance. DISCUSSION: Cases of Kossard's type scarring alopecia affecting premenopausal women made us consider that this condition is not exclusive of postmenopausal women. Differential diagnosis should take into account conditions like female androgenetic alopecia, fibrosing alopecia in a pattern distribution, alopecia areata, and chronic lupus erythematosus. Except for the pattern of alopecia, lichen planopilaris and frontal fibrosing alopecia are indistinguishable, thus the latter is included as a variant of lichen planopilaris. Although the disease tends to spontaneous stabilization, intralesional and topical corticosteroids, and anti-androgens may stop the progression of the disease and improve the female androgenetic alopecia that usually is associated to FFA.

Aged↗
PubMed2004

Increased expression of the gene for the Y1 receptor of neuropeptide Y in the amygdala and paraventricular nucleus of Y1R/LacZ transgenic mice in response to restraint stress.

A sustained increase in the brain concentrations of neuroactive steroids was previously shown to induce Y1 receptor gene expression in the amygdala of Y1R/LacZ transgenic mice which harbour a construct comprising the murine Y1 receptor gene promoter and the lacZ reporter gene. We now investigated the effects of restraint stress on both the cerebrocortical concentrations of neuroactive steroids and Y1 receptor gene expression in the amygdala and hypothalamic paraventricular nucleus (PVN) of Y1R/LacZ transgenic mice. The cerebrocortical concentrations of allopregnanolone and allotetrahydrodeoxycorticosterone were significantly increased immediately after a 1-h exposure to restraint stress and had returned to control values within 30 min. Expression of Y1R/LacZ was increased in the amygdala and PVN 6 h after restraint. The 5alpha-reductase inhibitor finasteride, that prevented the increase in neuroactive steroid concentrations, did not block that in transgene expression induced by 1-h restraint. Daily exposure to restraint for 10 days also increased the cerebrocortical concentrations of neuroactive steroids but failed to affect transgene expression. Acute but not repeated restraint thus increases Y1 receptor gene expression in the amygdala and PVN, suggesting that tolerance develops towards this stressor. The effect of acute restraint is not mediated by the increase in the brain concentrations of neuroactive steroids but may rather reflect a ligand-induced increase in Y1 receptor gene transcription. Data support a role of Y1 receptors in the behavioural and neuroendocrine responses to stress.

Amygdala↗
PubMed2005

The acute anticonvulsant effects of deoxycorticosterone in developing rats: role of metabolites and mineralocorticoid-receptor responses.

PURPOSE: The mechanisms that mediate the acute anticonvulsant effects of deoxycorticosterone (DOC) were investigated in young rats. METHODS: Fifteen-day-old rats were pretreated with a variety of compounds, including (a) agonists of the receptors that bind DOC (mineralocorticoid receptors); (b) the DOC 5alpha- and 5alpha-3alpha-reduced metabolites, plus agonists that bind the receptors of the 5alpha-reduced metabolite of DOC (progesterone receptors); and (c) DOC itself in the presence and absence of metabolism and receptor blockers. Fifteen minutes later, pentylenetetrazol (PTZ) was administered, and maximal pentylenetetrazol (MMT) seizure responses were scored. RESULTS: Agonists of mineralocorticoid receptors increased the latency to forelimb flexion in PTZ seizures and sometimes suppressed the seizures completely. At low, nonconvulsant doses, spironolactone (a mineralocorticoid-receptor antagonist) blocked the anticonvulsant effects of a nonsedating, but not a sedating, dose of DOC. These data suggest the possible direct involvement of mineralocorticoid receptors in the anticonvulsant effects of DOC. At low, nonconvulsant doses, finasteride (which blocks the metabolism of DOC) partially blocked the protective effects of DOC, suggesting the contribution of metabolites to the anticonvulsant actions of DOC. Dihydrodeoxycorticosterone (DHDOC)-the first metabolite of DOC, an agonist at progesterone receptors, and an allosteric modulator of the gamma-aminobutyric acid (GABA)(A) receptor-and tetrahydrodeoxycorticosterone, a secondary metabolite of DOC and an allosteric modulator of the GABA(A) receptor, both blocked MMT seizures. CONCLUSIONS: These findings suggest that both DOC and its metabolites may contribute to the anticonvulsant effects seen in young rats, perhaps acting via interactions with several different receptors.

Animals↗
PubMed2004

Anticonvulsant activity of progesterone and neurosteroids in progesterone receptor knockout mice.

Many of the biological actions of progesterone are mediated through the progesterone receptor (PR), a nuclear transcription factor. Progesterone is well recognized to protect against seizures in animal models. Although this activity has been attributed to the progesterone metabolite allopregnanolone, a GABAA receptor-modulating neurosteroid with anticonvulsant properties, PRs could also play a role. Here, we used PR knockout (PRKO(-/-)) mice bearing a targeted deletion of the PR gene that eliminates both isoforms of the PR to investigate the contribution of the PR to the anticonvulsant activity of progesterone. The protective activity of progesterone was examined in female and male homozygous PRKO mice and isogenic wild-type controls in the pentylenetetrazol (PTZ), maximal electroshock, and amygdala-kindling seizure models. In all three models, the anticonvulsant potency of progesterone was undiminished in PRKO mice compared with control mice. On the contrary, there was a substantial increase in the anticonvulsant potency of progesterone in the PTZ and kindling models. The antiseizure activity of progesterone in PRKO mice was reversed by pretreatment with finasteride, a 5alpha-reductase inhibitor that blocks the metabolism of progesterone to allopregnanolone. Unlike progesterone, the neurosteroids allopregnanolone and allotetrahydrodeoxycorticosterone exhibited comparable anticonvulsant potency in PRKO and wild-type mice. The basis for the heightened progesterone responsiveness of PRKO mice is not attributable to pharmacokinetic factors, because the plasma allopregnanolone levels achieved after progesterone administration were not greater in the PRKO mice. These studies provide strong evidence that the PR is not required for the antiseizure effects of progesterone, which mainly occurs through its conversion to the neurosteroid allopregnanolone.

Animals↗
PubMed2006

Neurosteroids involved in regulating inhibition in the inferior colliculus.

Fast inhibitory neurotransmission in the brain is largely mediated by the gamma-aminobutyric acid-type A (GABA(A)) receptor. The 3alpha,5alpha-reduced neurosteroids (e.g., allopregnanolone) are the most potent endogenous modulators of the GABA(A) receptor. Although it is known that 3alpha,5alpha-reduced neurosteroid levels change during stress or depression and over the estrus cycle, a basic physiological role consistent with their pharmacological action remains elusive. We used the unique architecture of the auditory midbrain to reveal a role for 3alpha,5alpha-reduced neurosteroids in regulating inhibitory efficacy. After blocking the massive GABAergic projection from the dorsal nucleus of the lateral lemniscus (DNLL) to the contralateral central nucleus of the inferior colliculus (ICC) in anesthetized rats, a reactive increase in the efficacy of other inhibitory circuits in the ICC (separable because of the dominant ear that drives each circuit) was demonstrated with physiological measures-single-neuron activity and a neural-population-evoked response. This effect was prevented by blocking 3alpha,5alpha-reduced neurosteroid synthesis with a 5alpha-reductase inhibitor: finasteride. Immunohistochemistry confirmed that the DNLL blockade induced an increase in 3alpha,5alpha-reduced neurosteroids in the contralateral ICC. This study shows that when GABAergic inhibition is reduced, the brain compensates within minutes by locally increasing synthesis of neurosteroids, thereby balancing excitatory and inhibitory inputs in complex neural circuits.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2001

Initial choices and final outcomes in lower urinary tract symptoms.

Management of lower urinary tract symptoms (LUTS) suggestive of benign prostatic hyperplasia (BPH) requires careful thought so that the most appropriate treatment can be targeted to each individual patient. Initial choices in the management of LUTS/BPH include watchful waiting, medical therapies and surgical interventions. A decision on treatment choice should be taken together with the patient. It should be based on the best available scientific evidence but also be individualised to patients' circumstances and personal choices. Management of LUTS/BPH should be focused on the burden and impact of urinary symptoms and related quality of life. The rate of treatment failure, which can be assessed through the switch to other medical therapy or surgery and/or the delay or prevention of complications related to LUTS/BPH, is also important. Beneficial effects of treatment should be balanced against the incidence of adverse events associated with therapy. Medical therapy has been shown to be effective in improving short-term outcomes (maximum urinary flow rate and symptom scores). Increasing evidence indicates that in the long-term more selective alpha(1)-adrenoceptor (AR) antagonists such as alfuzosin and tamsulosin may reduce the risk of treatment failure with a comparable rate to finasteride. Although the different alpha(1)-AR antagonists are equivalent in efficacy they differ in tolerability with the subtype selective tamsulosin having the lowest risk for interference with blood pressure regulation. Transurethral resection of the prostate (TURP) improves storage symptoms to a lesser extent and/or more slowly than it improves voiding symptoms. In contrast, alpha(1)-AR antagonists improve both voiding and bothersome storage symptoms to the same extent and quite rapidly which has a considerable impact on quality of life. alpha(1)-AR antagonists also relieve storage symptoms to almost the same extent as TURP. Ultimately the initial choice of treatment will depend upon its efficacy, speed of onset, durability, tolerability and on patients' choice. For the majority of patients with moderate to severe symptoms a subtype selective alpha(1)-AR antagonist such as tamsulosin offers the best current combination of efficacy and tolerability.

Adrenergic alpha-Antagonists↗
PubMed1998

Obstructive benign prostatic hyperplasia: therapeutical aspects.

OBJECTIVE: Once benign prostatic obstruction (BPO) is diagnosed, the urologist is confronted with an array of therapeutic modalities, from which he has to choose. The decision can be based on the patient's desire, deobstructing efficacy, durability, cost and on the physician's experience as well as availability of modalities. METHODS: A therapeutic spectrum is constructed for individualization of therapeutic options in evaluation of the relevant factors based on the published studies. RESULTS: In treating BPO the surgical treatment (TURP, TUIP) is still the most reliable in experienced hands, and its cost-efficacy has to be weighed against durability. If LUTS without intravesical obstruction dominates, alpha-blocker or finasteride (prostates >40 g) are useful and more efficient than watchful waiting when symptom relief and uroflow improvement are outcome parameters. Interventional treatment modalities remain a moving target, since even high-energy TUMT does not overcome obstruction. Ablation techniques (Holmium laser, TEVAP) have not been used with regard to durability. CONCLUSION: Picking an inappropriate modality or selecting the wrong patient may lead to a cascade of therapies. One can obtain a change in paradigms to measure the outcome putting emphasis on cost, need to retreat and, last but not least, quality of life.

Adrenergic alpha-Antagonists↗
PubMed1994

Effect of 5-alpha-reductase inhibition on sex-hormone-binding globulin in elderly men.

In this study we examined the possibility that chronic reduction in serum dihydrotestosterone (DHT) attained by pharmacologic inhibition of 5 alpha-reductase modulates serum sex-hormone-binding globulin (SHBG) levels in elderly men. Twenty-one men, ages 58-79 years (mean 66) with benign prostatic hypertrophy were treated with the 5 alpha-reductase inhibitor finasteride (5 mg daily) for 12 months. Serum DHT declined by 80% (p < 0.001) and total testosterone rose by 14% (p < 0.05). Serum SHBG concentration remained unchanged (44.1 +/- 4.5 vs 45.2 +/- 5.7 nmol/l for pre- and post-therapy levels, respectively). Thus, the conversion of testosterone to DHT is not required to maintain the androgenic effect on serum SHBG concentration in elderly men.

Aged↗
PubMed2000

Benign prostatic hyperplasia and erectile dysfunction--is there a link?

There is little evidence to support a link between benign prostatic hyperplasia (BPH) and erectile dysfunction (ED). Any apparent relationship may reflect the fact that both are common conditions with a similar gender and age distribution. However, the surgical treatment of BPH (e.g. TURP or open prostatectomy) may cause ED as a postoperative complication in some patients. Similarly, the medical treatment of BPH with finasteride may be associated with ED (< 5% in one study). However, alpha-blockade is not associated with this side-effect.

Adrenergic alpha-Antagonists↗
PubMed2005

Prevention of hormone-related cancers: prostate cancer.

Androgens are known to play an important role in normal prostate development, benign prostatic hyperplasia, established prostate cancer, and in prostate carcinogenesis. However, despite convincing experimental and clinical evidence, the epidemiologic data correlating sex steroid levels with disease risk is inconsistent. More recent work has focused on studies of polymorphisms in germ-line DNA in an effort to develop polygenic models of prostate cancer susceptibility and prognosis. Such models have the potential to aid in the selection of men for specific chemopreventive interventions and to help determine which men with localized prostate cancer are most likely to benefit from aggressive therapy. In this review, we will provide a brief summary of androgen metabolic pathways followed by an assessment of the epidemiology literature addressing the relationship between androgens and prostate cancer. Finally, we will address the two major questions that have arisen in response to the recently published results from the Prostate Cancer Prevention Trial: Who are the best candidates for finasteride chemoprevention, and what are the clinical implications of the high prevalence of prostate cancer that was detected in men with prostate-specific antigen levels in the so-called "normal" range?

Androgens↗
PubMed2001

Dietary supplement use in the Prostate Cancer Prevention Trial: implications for prevention trials.

Nutrients included in commonly used dietary supplements, such as vitamins C and E, may affect cancer risk. To better understand how supplement use may affect the interpretation of cancer prevention trials, we examined dietary supplement use among participants in the Prostate Cancer Prevention Trial, a double-blind, placebo-controlled trial of the drug finasteride (Proscar) for the primary prevention of prostate cancer. Of 15,387 men who completed food frequency questionnaires and dietary supplement questionnaires, 44.3% used a multivitamin, 35% used single supplements of vitamin C or E, and 10-15% used antioxidant mixtures or single supplements of vitamins A and D, zinc, or beta-carotene at least three times per week. The strongest correlates of supplement use were higher education and lower body mass index (p < 0.001), and whites and Asians were more likely to use multivitamins and single supplements of vitamins C and E than were blacks and Hispanics. Supplement users obtained 87% of their total daily vitamin E intake, 61-64% of vitamins A, C, and D, and about half of beta-carotene, folate, and zinc from supplements. Because supplements, especially antioxidants, may confer independent cancer-preventive effects, analytic models of study findings should include exposure measurement of dietary supplements with appropriate tests for interaction. Our results can be generalized to similar chemoprevention trials.

Aged↗
PubMed1989

The effect of a 5 alpha-reductase inhibitor on androgen physiology in the immature male rat.

To provide insight into the role of 5 alpha-dihydrotestosterone (DHT) in postnatal androgen physiology, we administered the 5 alpha-reductase inhibitor finasteride to male rats from birth through the onset of puberty. In 4-week-old control rats serum testosterone levels averaged 0.21 ng/ml, and DHT levels averaged 0.64 ng/ml. By 7 weeks of age, testosterone levels increased more than 7-fold to 1.57 ng/ml, while the circulating DHT level declined to 0.26 ng/ml. In both the 4- and 7-week-old inhibitor-treated animals, circulating DHT levels were 25-50% of control values, and circulating testosterone levels were higher than control values. In 7-week-old inhibitor-treated rats, the weights of prostate, penis, seminal vesicles, and epididymal tissues were only 30-50% those of the controls. However, DHT formation is apparently not critical for postnatal development of the preputial glands or the androgen-dependent perineal muscles, since the weights of these tissues were not affected by treatment with inhibitor. Treatment with the 5 alpha-reductase inhibitor had no apparent effect on testicular histology or daily sperm production despite the fact that testicular DHT content was lower (70%) and testosterone content was higher (250%) than those in controls. We conclude that DHT formation is important for the normal postnatal growth of the prostate, seminal vesicles, epididymis, and penis and may be important for normal feedback control of testosterone production in rats, but that its formation is not critical for the onset of spermatogenesis or the development of the preputial glands or the androgen-dependent perineal muscles.

5-alpha Reductase Inhibitors↗
PubMed1995

Androgens rapidly increase the cytosolic calcium concentration in Sertoli cells.

We demonstrate that androgens rapidly and specifically increase intracellular calcium in Sertoli cells, investigate the mechanism, and suggest the unifying hypothesis that calcium might be a common intracellular molecular effector to explain the known synergism between FSH and testosterone (T) action on Sertoli cells in support of spermatogenesis. In freshly isolated Sertoli cells, T and its 5 alpha-reduced metabolite dihydrotestosterone increased intracellular calcium from 83 +/- 4 to 147 +/- 8 and 167 +/- 29 nM, respectively, whereas estradiol had minor (117 +/- 9 nM) and progesterone no (80 +/- 6 nM) effect. The effect of T was rapid (20-40 sec) and inhibited by 1) preincubation with either a pure nonsteroidal antiandrogen (hydroxyflutamide) or a 5 alpha-reductase inhibitor (finasteride) or 2) removal of extracellular calcium (47 +/- 4 nM) or pharmacological blockade of voltage-activated (62 +/- 5 nM) or voltage-independent (55 +/- 14 nM) membrane calcium channels. These findings suggest that the T-induced rise in Sertoli cell cytosolic calcium involves sequential 5 alpha-reduction, binding to a classical androgen receptor, and activation of transmembrane influx of extracellular calcium. Immobilization of T by conjugation to a large carrier molecule (BSA) to prevent steroid entry into Sertoli cells also resulted in a rapid increase in cytosolic calcium to a similar magnitude as unconjugated T, consistent with a plasma membrane site of action. This finding together with the rapid cytosolic calcium rise caused by T argues for the possible existence of a short term, nongenomic effects in hormonal regulation of Sertoli cell function in addition to the well known, slower genomic response.

Androgen Antagonists↗
PubMed2004

An update on the use of 5alpha-reductase inhibitors.

Twelve years ago, finasteride, the first 5alpha-reductase inhibitor, was introduced as drug therapy for benign prostatic hyperplasia, and more recently dutasteride has emerged as an alternative. The efficacy, safety and ability of these 5alpha-reductase inhibitors to reverse the natural progression of benign prostatic hyperplasia have been convincingly demonstrated and both drugs are now well established in the medical armamentarium against the disease. Given the multifactorial etiology of benign hyperplasia, the usefulness of 5alpha-reductase inhibitors in combination with alpha adrenergic blockers has also been investigated and justified in select patients. Wider applications of 5alpha-reductase inhibitors are also emerging, though their perhaps most important new role as chemopreventive agents remains unclear.

Adrenergic alpha-Antagonists↗
PubMed2004

After ALLHAT: doxazosin for the treatment of benign prostatic hyperplasia.

Doxazosin mesylate is an alpha1-adrenoceptor antagonist that was used to treat hypertension until a major study (ALLHAT; Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial) showed that it increased the risk of progressing to heart failure. Doxazosin is now being used to treat benign prostatic hyperplasia (BPH). Noradrenaline acts on alpha1-adrenoceptors to contract the smooth muscle in the prostate and bladder, and by opposing these actions, doxazosin is beneficial in BPH. Doxazosin also increases apoptosis in the prostate. Although the standard preparation is suitable for once-daily dosing in BPH, it has to be titrated through three steps to its final dose. The controlled-release gastrointestinal therapeutic system (GITS) formulation of doxazosin is more convenient to use as it only has to be titrated through one step. In the treatment of BPH, standard doxazosin reduced both obstructive and irritative symptoms and increased peak urinary flow rate. The main side effects with doxazosin are those commonly associated with lowering blood pressure, although doxazosin lowers blood pressure to a lesser extent in normotensives than hypertensives. There is some evidence that in addition to being easier to use, doxazosin GITS may cause less adverse effects than the standard preparations. The benefits of doxazosin and the 5alpha-reductase inhibitor, finasteride, may be additive in BPH especially in men with large prostates. Further trials are necessary in order to determine whether doxazosin GITS is superior to other alpha1-adrenoceptor antagonists in BPH.

5-alpha Reductase Inhibitors↗
PubMed1998

Androgens and masculinization of genitalia in the spotted hyaena (Crocuta crocuta). 2. Effects of prenatal anti-androgens.

Pregnant spotted hyaenas were treated with anti-androgens to interfere with the unusually masculine 'phallic' development that characterizes females of this species. The effects on genital morphology and plasma androgen concentrations of infants were studied during the first 6 months of life. Although there were consistent 'feminizing' effects of prenatal anti-androgen treatment on genital morphology in both sexes, such exposure did not produce males with extreme hypospadia, as it does in other species, nor did it produce females with a 'typical' mammalian clitoris and external vagina. 'Feminization' of males resulted in a penis with the morphological features of the hyaena clitoris, and 'feminization' of females exaggerated the sex differences that are typical of this species. The effects of treatment were present at birth and persisted for at least 6 months. Treatment of pregnant females with flutamide and finasteride also markedly reduced circulating concentrations of testosterone and dihydrotestosterone in maternal plasma during pregnancy. Plasma delta 4-androstenedione was reduced in the female, but not the male, infants of treated mothers, consistent with an epigenetic hypothesis previously advanced to explain hormonal 'masculinization' of females. The present 'feminizing' effects of prenatal anti-androgen treatment are consistent with contemporary understanding of sexual differentiation, which accounts for morphological variation between the sexes in terms of steroids. However, current theory does not account for the basic genital structure of females and the present data suggest that development of the male penis and scrotum, and the female clitoris and pseudoscrotum, in spotted hyaenas may involve both androgen-dependent and androgen-independent components.

5-alpha Reductase Inhibitors↗
PubMed2006

Deiodinase type 1 activity is expressed in the prostate of pubescent rats and is modulated by thyroid hormones, prolactin and sex hormones.

The aim of this study was to characterize the type of 5'-deiodinase activity in the prostate of pubescent rats (7-8 weeks), to establish its distribution in the lobes (ventral, dorsolateral, and anterior), and to analyze its modulation by prolactin (PRL), testosterone, dihydrotestosterone (DHT), and 17beta-estradiol (E(2)). Our results showed that the enzymatic activity was highly susceptible to inhibition by 6-n-propyl-2-thiouracil and gold thioglucose, its preferential substrate was reverse tri-iodothyronine (rT(3)), it exhibited a low dithiothreitol requirement (5 mM), and the apparent K(m) and V(max) values for substrate (rT(3)) were approximately 0.25 microM and 9.0 pmol liberated/mg protein per hour, respectively. All these characteristics indicate the preferential expression of type 1 deiodinase (D1), which was corroborated by demonstrating the presence of D1 mRNA in prostate. D1 activity was detected in all lobes and was most abundant in the dorsolateral. Although we detected type 2 deiodinase (D2) mRNA expression, the D2 activity was almost undetectable. D1 activity was enhanced in animals with hyperthyroidism and hyperprolactinemia, in intact animals treated with finasteride (inhibitor of local DHT production), and in castrated animals with E(2) replacement. In contrast, activity diminished in castrated animals with testosterone replacement. Our results suggest that thyroid hormones, PRL, and E(2) exert a positive modulation on D1 activity, while testosterone and DHT exhibit an inhibitory effect. D1 activity may be associated with prostate maturation and/or function.

Animals↗