Accessory Sex Organs Research Articles

Pharmacological and toxicological assessment of a potential GnRH vaccine in young-adult male pigs

Active immunization against gonadotrophin-releasing hormone (GnRH) is successfully applied to prevent boar taint in pork. In men, GnRH immunization could be an alternative to hormone therapy in patients with prostate cancer. In this study, a new GnRH vaccine formulation (a modified GnRH peptide conjugate formulated with CoVaccine adjuvant) was investigated for its pharmacological efficacy and safety in young-adult male pigs. Immunization resulted in castrate-like plasma testosterone levels in all treated pigs from week 8 until the end of the study, 30 weeks after the first immunization. Testosterone depletion retarded testes growth, reduced the relative weight of the testes and accessory sex organs, and reduced sperm counts and motility. There was no clinically relevant toxicity. Typical vaccination-related adverse reactions, such as swelling at the injection site and fever, were considered acceptable. We conclude that this GnRH vaccine efficiently and rapidly reduced serum testosterone levels, without inducing chronic toxic effects, and therefore could be applicable in both veterinary and human medicine.

Effects of Triclocarban on Intact Immature Male Rat: Augmentation of Androgen Action

Triclocarban (TCC; 3,4,4'-trichlorocarbanilide) is an antimicrobial agent used widely in various personal hygiene products including soaps. Recently, TCC has been shown to enhance testosterone-induced effects in vitro and to enlarge accessory sex organs in castrated male rats. This study was designed to evaluate the effects of TCC on intact age-matched male rats and on human prostate LNCaP and C4-2B cells. Seven-week-old male Sprague-Dawley rats received either a normal diet or a diet supplemented with TCC (0.25% in diet) for 10 days. Triclocarban induced hyperplasia of accessory sex organs in the absence of significant qualitative histological changes. Serum luteinizing hormone (LH) and testosterone were not significantly altered by TCC treatment. In prostate cancer-derived LNCaP and C4-2B cells, TCC potentiated androgen actions via androgen receptor-dependent actions. In conclusion, TCC significantly affects intact male reproductive organs and potentiates androgen effects in prostate cancer cells.

Effects of Cynodon dactylon on Stress-Induced Infertility in Male Rats

Cynodon dactylon (Family: Poaceae) is known to be a tackler in Indian mythology and is offered to Lord Ganesha. It is found everywhere, even on waste land, road side, dry places, and spreads vigorously on cultivated ground. This study was carried out with an objective to test if the constituents of this plant are useful in coping stress-induced sexual In this study, we considered immobilization stress to induce male infertility and the effect of C. dactylon in restoration of the dysfunction was evaluated by considering sexual behavioral observations, sexual performance, fructose content of the seminal vesicles, epididymal sperm concentration and histopathological examinations as parameters. Treatment of rats under stress with methanolic extract of C. dactylon has shown a promising effect in overcoming stress-induced sexual dysfunction, sexual performance, fructose content, sperm concentration and its effect on accessory sexual organs and body weight. We conclude that active constituents of C. dactylon present in methanolic extract have a potent aphrodisiac and male fertility activity.

Impact of Finasteride on Stroma of Benign Hyperplasia of Prostate

Benign prostatic hyperplasia (13P11) is a hyperplastic process of the strontal and epithelial cells of the prostate due to effect of male sex hormone testosterone. Testosterone is the main male sex hormone, responsible for growth of sexual character and accessory sex organs. Despite its effectiveness as an male sex hormone, it causes benign prostatic hyperplasia (BM resulting in urinary dysfunction. On the other hand, finasteride. a 4-azastroid, inhibits the hyperplastic effect of testosterone and benign prostatic hyperplasia. The objective of the study was to observe the effects of finasteride on the stroma of testosterone induced prostatic hyperplasis in long Evans rats. This experimental study was carried out in the Department of Anatomy, Sir Salimullah Medical College, Dhaka from January to December 2006. Total 45 matured male long Evans rats of age 8-10 weeks and weighing 200-300 gm were used in this study. They were divided into three equal groups. Group A was vehicle (olive oil) control group, Group 13 was testosterone treated group and Group C was testosterone and finasteride treated group. The rats were sacrificed on the eleventh day. It was concluded that finasteride is an effective drug that successfully inhibits the testosterone induced prostatic hvperplasia

Effect of Metronidazole on Spermatogenesis, Plasma Gonadotrophins and Testosterone in Male Rats

Metronidazole and it’s derivatives are drugs that have both antiprotozoal and anti bacterial effect.The reproductive toxicity of metronidazole has been shown in some studies. To investigate the effect of metronidazole on spermatogenesis in adult male rats, this study was designed. Eighteen wistar male rats (70-90days old) were randomly divided into three groups. Animals in group I (Control group) were administered the water. Animals in groups II, III were administered metronidazole at doses of 200 and 400 mg/kg/day for 60 days. Different varieties of germ cells at stage VII seminiferous epithelium cycle, namely, type A spermatogonia (ASg), preleptotene spermatocytes (pLSc) and step 7 spermatids (7Sd) were quantitatively evaluated, along with radioimmunoassay of plasma follicle-stimulating hormone (FSH), luteiniging hormone (LH), testosterone assessment. In the 200 and 400 mg/kg groups, there were significant decreases in the testes and accessory sex organ weights, plasma concentrations of LH, FSH and testosterone with massive degeneration of all the germ cells at stage VII. It is concluded that metronidazole has a suppressive influence on spermatogenesis and sex hormones in rats.

Effects of in Utero Exposure to DI(n-Butyl) Phthalate on Development of Male Reproductive Tracts in Sprague-Dawley Rats

The purpose of this study was to determine the effects of di(n-butyl) phthalate (DBP) administration on male reproductive organ development in F1 Sprague-Dawley rats following in utero exposure. During gestation days (GD) 10–19, pregnant rats were administered daily, orally, DBP at 250, 500, or 700 mg/kg or flutamide (1, 12.5, or 25 mg/kg/d) as a positive control. The male offspring were sacrificed at 31 d of age. DBP and flutamide dose-dependently significantly increased the incidence of hypospadias and cryptorchidism in F1 male offspring. The weights of testes and accessory sex organs (epididymides, seminal vesicles, ventral prostate, levator ani plus bulbocavernosus muscles (LABC), and Cowper's glands) were significantly reduced in DBP-treated animals. Furthermore, cauda agenesis of epididymides and ventral prostate atrophy were observed in high-dose 700-mg/kg DBP males. Anogenital distance (AGD) and levels of dihydrotestosterone (DHT) and testosterone were significantly decreased in the DBP (700 mg/kg/d)-treated groups. In particular, the expression of androgen receptor (AR) and 5α-reductase type 2 in the proximal penis was markedly depressed following administration of DBP (700 mg/kg/d) or flutamide (25 mg/kg/d). The expression of sonic hedgehog (Shh) in the urethral epithelium of the proximal penis was significantly less in the DBP (700 mg/kg/d)- or flutamide (25 mg/kg/d)-treated groups. In addition, DBP dose-dependently significantly increased the expression of estrogen receptor (ER α) in the undescended testis. Data demonstrated that in utero exposure to DBP produced several abnormal responses in male reproductive organs, and these effects may be due to disruption of the stage-specific expression of genes related to androgen-dependent organs development.

Effects of petroleum ether extract of Anacyclus pyrethrum DC. on sexual behavior in male rats

The roots of Anacyclus pyrethrum DC. (Compositae) are employed in Ayurvedic system of medicine as "Vajikaran Rasayana"--a category of drugs for vitality and virility. They are believed to have aphrodisiac action. The present investigation was undertaken to evaluate their effects on sexual behavior in male rats. Thirty-two male Wistar rats were divided into control group, testosterone group, low-dose (50 mg/kg) petroleum ether extract (PEE) group and high-dose (100 mg/kg) PEE group. PEE obtained from the roots of Anacyclus pyrethrum was administered orally to albino rats once daily, and 0.5 mg/kg (body weight) of testosterone was given intramuscularly twice weekly and served as positive control. The course of treatment was 28 days. The effects of PEE and testosterone on changes in body and accessory sexual organ weights, sexual behavior, penile erection and sexual performance were studied before treatment, after 15 and 28 days of treatment and 7 and 15 days after treatment. After 28 days of treatment, PEE and testosterone had a marked influence on body and accessory sexual organ weights as compared with arachis oil. The treated male rats were more receptive and oriented towards female rats and increased precopulatory activities like licking and sniffing of female anogenital were observed. The penile erection index was significantly increased with reduction in mount latency and intromission latency period. There were four-fold increase in mount and three-fold increase in intromission frequency in treated rats reflecting improved sexual performance. The behavioral and sexual parameters were also observed after a lapse of 7 and 15 days of discontinuance of drug treatment. Unlike testosterone, the PEE of Anacyclus pyrethrum shows efficacy in rats tested after the lapse of 7 and 15 days of discontinuation of treatment. This suggests that the drug has prolonged effect and capacitate the treated rats for improved sexual potential.

Luteinizing hormone reduction by the male potency herb, Butea superba Roxb.

To determine if Butea superba Roxb., a traditional Thai male potency herb, has androgenic activity in 60-day-old male Wistar rats, we measured its effects on the pituitary-testicular axis and sex organs. Intact and orchidectomized adult male rats were subdivided into five groups (10 rats/group): distilled water, Butea superba (BS)-10, BS-50, BS-250, and testosterone propionate (TP). They received 0, 10, 50, and 250 mg·kg body weight(-1)·day(-1) BS in distilled water by gavage and 6 mg·kg body weight(-1)·day(-1) TP sc, respectively, during the 30-day treatment period. Blood was collected every 15 days and luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone were measured. Changes of weight and histological appearance of sex organs were determined at the end of the 30-day treatment and 15-day post-treatment periods. TP treatment reduced serum FSH and LH levels and significantly increased the weight of the seminal vesicles and epididymis, in accordance with histopathological changes, in both intact and orchidectomized rats. No changes in serum testosterone, LH, and FSH levels were observed in any of the intact rats treated with BS, but a significant increase in seminal vesicle weight was observed only in the BS-250 group. Although a significant reduction in serum LH was detected in the BS-50 and BS-250 groups of orchidectomized rats, no significant change in weight or histology of sex organs was observed. Thus, we conclude that B. superba needs endogenous testosterone to work synergistically to stimulate the accessory sex organ of intact animals and can potentially exhibit an LH reduction effect in orchidectomized animals.

Effect of chronic oestrogen administration on androgen receptor expression in reproductive organs and pituitary of adult male rat

Following chronic (15 or 30 days) treatment with oestradiol 3-benzoate (75 microg rat(-1) day(-1) in 100 microl of olive oil) to adult rats, androgen receptor (AR) expression was analysed simultaneously in testis, epididymis, seminal vesicle, prostate and pituitary utilising three independent tools i.e. immunohistochemistry, Western blotting and RT-PCR. All the five organs showed higher AR transcriptional activity gradually increasing from 15 to 30 days of oestrogen treatment. However, the AR protein expression either through immunostaining or Western blotting demonstrated a significant decline in all the reproductive organs. In the pituitary, on the other hand, the decline coincided with a distinct breakdown of the AR protein into two bands with increasing duration of treatment. Serum and intra-testicular testosterone levels were found significantly lowered. Spermatogenesis was adversely affected with concurrent decrease in weights of testis and accessory sex organs. Decrease in testis weight was consistent with the reduction in the number of maturing germ cells per tubule. Despite the decrease in weight, accessory sex organs like epididymis, seminal vesicle and prostate were completely devoid of any apoptotic cells which were characterised only in testis and pituitary. Seminiferous epithelium demonstrated a marked increase in the number of germ cells undergoing apoptosis. However, the rate of cell apoptosis was much higher in the pituitary than in the testis at the end of 30 days treatment. It is therefore concluded that degradation of AR protein expression after oestrogen treatment is probably directly linked to an increase in cell apoptosis both in testis and pituitary.

Atypical Fetal Prostate Development is Associated with Ipsilateral Hypoplasia of the Wolffian Ducts in the ACI Rat

For over a half century, the ACI (August x Copenhagen) rat has been a primary model for studying renal agenesis and ipsilateral hypoplasia (IHP) of the Wolffian-derived structures (WDS). Because the ACI rat is also used as a model for prostate research, it is important to examine the relationship of IHP and urogenital sinus (UGS) development. The prostate is dependent on androgens for proper growth and differentiation. Alteration in androgen production and/or delivery to the UGS has the potential to perturbate normal development. In this study, we investigate whether the ipsilateral loss of the WDS is associated with altered prostate development. Digital images of serial-sectioned fetal ACI rat UGS were used to create three-dimensional (3-D) surface-rendered models of the developing prostate, seminal vesicle, vas deferens, and utricle on gestational day 21. The number and volume of prostate ducts developing from the UGS were calculated from the 3-D model data. Animals exhibiting IHP had a significant decrease in total fetal prostate volume (40%; P < 0.005) with significant regional specific differences when compared with normal male ACI rats. Anatomical and histological differences in the utricle, abnormal histology of the ipsilateral testes, and a truncation of the ipsilateral Wolffian ductal mesenchyme were also seen in the animals with IHP. Additional research is needed to further understand the mechanisms and consequences of IHP on prostate growth and development. Alterations to normal prenatal development of the male accessory sex organs can have important consequences for the growth and morphology of the adult gland.

Exercise and Supraphysiological Dose of Nandrolone Deconoate Increase Apoptosis in Spermatogenic Cells

Anabolic-androgenic steroids are used at high doses by athletes for improving athletic ability, physical appearance and muscle mass. Unfortunately, the abuse of these agents has significantly increased. It has been established that exercise and high doses of anabolic-androgenic steroids may influence the hypothalamic-pituitary-gonadal axis, which can in turn affect testicular apoptosis. However, the effect of the combination of exercise and high dose of anabolic-androgenic steroids on testicular apoptosis is not known. We investigated the combined effects of exercise and high doses of nandrolone decanoate on apoptosis in the spermatogenic cell lineage. Five groups of male Wistar strain albino rats were treated as follows for 8 weeks: solvent of nandrolone decanoate (peanut oil) as a vehicle (Sham); nandrolone decanoate (10 mg/kg/weekly) (nandrolone decanoate); exercise (1 hr/day, 5 days a week) (exercise); nandrolone decanoate (10 mg/kg/weekly) and exercise (1 hr/day, 5 days a week) (nandrolone decanoate exercise); and sedentary control without any injection or exercise (Control). Apoptosis in the male germ line was characterized by TUNEL, caspase-3 assay and transmission electron microscopy. The weights of the testis and accessory sex organs, as well as sperm parameters significantly decreased in the experimental groups relative to the sham and control groups (p < or = 0.05). Germ cell apoptosis and a significant decrease in the number of germ cell layers in nandrolone decanoate exercise-treated testes were observed (p < or = 0.05). Exercise training seems to increase the extent of apoptotic changes caused by supraphysiological dose of nandrolone decanoate in rats, which in turn affects fertility.

OECD validation of phase‐3 Hershberger assay using the stimulated weanling male rat in Korea

The OECD has proposed a new, validated test guideline with the stimulated weanling male Hershberger assay to avoid the surgical castration step. In the present study, we assessed the relevance and reliability of the stimulated weanling Hershberger assay in four stages. All chemicals except for testosterone propionate (TP) were orally administered to sexually immature male rats of 22 days old for 10 days. The weights of four mandatory accessory sex organs, two additional reproductive tissues and optional systemic organs were evaluated. At the first two stages, TP, as reference androgen, significantly increased the weights of epididymides and accessory sex organs (ASO) at 1.0 mg kg(-1) and flutamide (FLU), as a positive anti-androgen control, decreased the TP-stimulated organ weights at 3.0 mg kg(-1). At stage 3, trenbolone (40 mg kg(-1)), an anabolic steroid, significantly increased ASO weights, and weak anti-androgens (DDE and linuron) decreased the TP-stimulated ASO weights at each high dose. The above results were confirmed in a blind test with coded substances provided by OECD. Compared with results from our previous castrated male assay, the intact weanling version is less sensitive than the castrated male version, in terms of a smaller response at the reference dose of TP or FLU. However, this study suggests that the stimulated weanling Hershberger assay can detect the effects of both potent and weak anti-androgens on androgen-producing and androgen-dependent tissues.

Vitamin E-supplementation protect chromium (VI)-induced spermatogenic and steroidogenic disorders in testicular tissues of rats

Excess chromium (Cr) exposure is associated with various pathological conditions including reproductive dysfunction. Generation of oxidative stress is one of the plausible mechanisms behind Cr induced cellular deteriorations. The efficacy of vitamin E to combat Cr induced oxidative damage in adult rat testis has investigated in the current study. Adult male rats exposed to hexavalent Cr (intraperitoneal injection with 0.4mg K2Cr2O7/kgbw/day) for 26days resulted in decreased accessory sex organs weight compared to controls. Development of oxidative stress in testis was evidenced by increased lipid peroxidation along with decreased superoxide dismutase (SOD) and catalase activities than control animals. Marked reduction in the activities of testicular steroidogenic enzymes; Δ53β-hydroxysteroid dehydrogenase (HSD), 17β-HSD, serum testosterone and Leutinizing Hormone (LH) levels were observed. However significant increase in serum Follicle Stimulating Hormone (FSH) level was observed with Cr treated group. Histological evaluation of testis revealed degeneration of stage VII spermatogenic cycle along with decrease in epithelial cell height in epididymis and seminiferous tubules; number of different germ cells per seminiferous tubule and seminiferous tubular diameter reduced after Cr exposure. Simultaneous oral supplementation of vitamin E (50mg/kgbw/day) in Cr exposed rats showed less oxidative damage and restored the otherwise altered testicular activities. Epididymal sperm number was also restored in vitamin E-supplemented group than Cr induced rats. This study implicates vitamin E as a possible protective agent against Cr induced spermatogenic and steroidogenic alteration.

Role of Flutamide on Acinar Diameter in Testosterone Induced Prostatic Hyperplasia

Testosterone is the male sex hormone responsible for growth of secondary sexual characters and accessory sex organs. Despite the effectiveness as a male sex i101711011C, testosterone causes benign preemie hyperplasia (BPH) resulting in urinary dysfinction. On the other hand. Bromide is a pure anthestosterone, which blockw the effects of dihydnoestosterone (DHT)at the testosterone receptor and presents BM. The objective of the study was to observe the effects of flutamide on testosterone induced promatic hypetplasia in Long Evans rats. This experimental study was carried or I e Department of Anatomy. Sir Salimullah Medical College. Dhaka from January to December 2006. Forty five matured male Long Evans rats of age 8-10 weeks and weighing 200-300 gnu were used in this study. They were divided into three equal groups. Group A was vehicle (olive oil) control group. Group B was testosterone treated group and Group C was testosterone and flu:amide treated group. Comparative study in different groups were done microscopically. There was significant reduction (p&lt;0.001) qproslatic hypetplasia. The mean diameter of acini of prostate in flutamide treated rats was loner than the testosterone treated rats. It can be concluded from this study that flatamide is an effective drug against testosterone induced prostatic hyperplasia.

The aromatase inhibitor 1,4,6-androstatriene-3,17-dione (ATD) reduces disinhibitory behavior in intact adult male rats treated with a high dose of testosterone

Anabolic androgenic steroids and high testosterone doses have been reported to induce impulsive behavior in man and behavioral disinhibition in rats. The purpose of the present study was to investigate whether aromatization of testosterone to estradiol is of importance for the behavioral disinhibiting effect of a high testosterone dose in adult male rats. Testosterone administered via five testosterone-filled silastic capsules implanted subcutaneously (s.c.) to non-castrated, group-housed rats for six days induced behavioral disinhibition in a modified Vogel's drinking conflict model and yielded supraphysiological serum levels of testosterone and increased accessory sex organ weights. Moreover, concurrent administration of the aromatase inhibitor 1,4,6-androstatriene-3,17-dione (ATD; 60mg/kg/day s.c.) decreased behavioral disinhibition in testosterone-treated rats (without affecting accessory sex organ weights) while behavior was not significantly affected in sham-treated animals. Since some reports indicate that ATD, in addition to inhibit aromatase, also may affect the binding of testosterone to the androgen receptor, the effect of the non-steroidal androgen receptor antagonist flutamide was investigated. Flutamide treatment did not affect disinhibited behavior in testosterone-treated rats. However, in sham-treated animals, flutamide (50mg/kg/day) produced behavioral disinhibition. These results suggest that estradiol is of importance in the mechanisms underlying behavioral disinhibition in non-castrated rats treated with a high testosterone dose. Speculatively, aromatization may be involved in pro-impulsive effects of high testosterone doses in humans.

Postnatal treatment of human seminal plasma inhibin: gonadotropin and prolactin levels during the onset of puberty in the rat.

Plasma gonadotrophin and prolactin levels, pituitary and accessory sex organ weights were evaluated on day 40 in rats of either sex treated with human seminal plasma (HSP) inhibin on day 7, 15, 21 and 30 postnatally. HSP inhibin suppressed both FSH and LH but without any effect on plasma PRL levels. The weights of pituitary and accessory sex organs were significantly suppressed. These results indicate a role for inhibin in the postnatal gonadotrophin release and a possible direct action on the accessory reproductive organs in the rat.

The Effect of Estrogen Analogues on the Development of the Testis, Epididymis, and Penis in Rats.

Studies suggest that the use of ethinyl estradiol (EE), a semi-synthetic estrogen used in oral contraceptives, may have adverse effects on the development of the male reproductive tract. The objective of the current study was to determine the effects of neonatal exposure of EE on the penis, accessory sex organs and serum testosterone in rats. Neonatal male rats were administered one of the following treatments: 0ng EE (n=5), 10ng EE (n=5), 100ng EE (n=5), 1μg EE (n=4), or 10 μg EE (n=6) on postnatal days (PND) 2, 4, 6, 8, 10 and 12. On d50, the animals were sacrificed and the penis, seminal vesicle, epididymis and serum testosterone was evaluated. Testicular weights showed a linear decline with increased EE at 3.59g, 3.37g, 3.03g, 2.41g, and 1.39g, respectively. Similarly, epididymal head and body weights showed a linear decline with increased EE at 0.68g, 0.64g, 0.57g, 0.49g and 0.312g, respectively. Epididymal tail weights followed a similar trend with increased EE at 0.49g, 0.46g, 0.45g, .035g and 0.319g, respectively. Further, penis length and penis weight declined linearly with increased EE from 41mm to 29mm and 0.290g to .092g, respectively. These findings support the hypothesis that neonatal exposure to estrogens can negatively affect proper reproductive tract development in rats. This is of great importance, as PND one to six in rats corresponds to the first trimester in humans, suggesting that in utero exposure to estrogens, such as EE, may have pleiotropic effects on the development of the male reproductive tract. (poster)

The Reproductive Biology of the Cave Myotis (Myotis velifer)

This study examines the anatomical structure, function and seasonal cyclicity of the male and female reproductive organs of the cave myotis (Myotis velifer) in Texas and southern Arizona. The data indicated that this is a monestrous, seasonally breeding species that stores spermatozoa in both sexes during extended winter torpor or hibernation. The male reproductive cycle was characterized by asynchronous function of the testes (spermatogenesis) and accessory sex organs. Structural factors in both sexes and fructose levels in male accessory organs were evaluated for their significance in prolonged spermatozoa storage. The reproductive anatomy and chronology were similar to other temperate-dwelling vespertilionid bats. Dextral dominance was a feature of the female reproductive tract.

Alterations in carbohydrate metabolism under cryptorchid condition in albino rats

Bilateral cryptorchidism was induced surgically in adult wistar strain albino rats and the carbohydrate metabolic pathway has been studied in testis, and sex accessory organs of both control and cryptorchid animals by estimating the marker enzymes and the substrates of the metabolism. In cryptorchid animal tissues, accumulation of lactic acid and glycogen was observed with inhibited phosphorylase activity in comparison to the controls. The reproductive tissues like testis, epididymis, prostate gland and seminal vesicles had shown remarkable elevation in the glycogen content, which can be attributed to decreased phosphorylase activity. In view of androgen dependent nature of phosphorylase its inhibition can be correlated to decreased testosterone circulation in the body. Consequently the free glucose content of the tissues was markedly decreased suggesting a decrease in the mobilization of the carbohydrates into energy metabolism. All the reproductive tissues had shown significant accumulation of lactic acid with inhibited oxidative enzyme activities. Thus the reproductive tissue oxidative metabolism had been suppressed during cryptorchidism leading to a shift towards glycolysis and creating a situation of functional suppression.

Blockade of α 1A-adrenoceptor: A novel possible strategy for male contraception

Worldwide almost one quarter of all couples practicing contraception rely on male methods. However, currently available options for male contraception are limited. Thus, it is urgent to develop safe, effective, and reversible male contraceptives. To date, alpha(1)-blockers are the most widely used agents for the treatment of benign prostatic hyperplasia. Several studies reveal that in elderly patients the alpha(1A)-selective antagonist tamsulosin can induce a notably high incidence of ejaculation dysfunction characterized by low ejaculate volume. Recent clinical trials suggest that tamsulosin may effectively inhibit sperm ejaculation in young volunteers. Since alpha(1A)-adrenoceptor subtype plays a dominant role in mediating the contractions of accessory sex organs contributing to ejaculation, we hypothesize that blockade of alpha(1A)-adrenoceptor may suppress the motility of these organs, thereby inhibiting sperm transport and achieving contraception, and the alpha(1A)-selective antagonists can act as a male contraceptive. If our hypotheses can be further supported with clinical trials it will shift the paradigm for male-based contraception and provide a wider range of choice for all.