Differential patterns of liver proteins in experimental murine hepatosplenic schistosomiasis.

Schistosoma mansoni eggs produced by adult worms in the mesenteric vasculature become trapped in the liver, where they induce granulomatous lesions and strong immune responses. Infected individuals suffer from intestinal schistosomiasis (INT) in 90% of cases, whereas the remaining 10% present with severe hepatosplenic schistosomiasis (HS). The CBA/J mouse model mimics human disease, with 20% of infected mice developing hypersplenomegaly syndrome (HSS) that resembles HS and 80% developing moderate splenomegaly syndrome (MSS) similar to INT. We studied differential patterns of protein expression in livers of 20-week-infected CBA/J mice with MSS or HSS to understand the molecular changes that underlie these two disease forms. Using differential in-gel electrophoresis to identify differentially expressed protein spots, we found 80 protein spots significantly changed with infection and 35 changes specific to severe disease. In particular, the abundances of prohibitin 2, transferrin isoforms, and major urinary protein isoforms were significantly altered in HSS mice. Furthermore, annexin 5, glutathione S-transferase pi class, and S. mansoni phosphoenolpyruvate carboxykinase expression levels changed significantly with schistosome infection. Additionally, levels of major urinary protein decreased and levels of transferrin increased significantly in the sera of HSS mice compared to levels in sera of MSS or control mice, and these differences correlated to the degree of splenomegaly. These findings indicate that the liver protein abundances differ between MSS and HSS mice and may be used for the development of diagnostic markers for the early detection of hepatosplenic schistosomiasis.

Sperm characteristics and teratology in rats following vas deferens occlusion with RISUG and its reversal.

The functional success of the reversal of vas occlusion by styrene maleic anhydride (RISUG), using the solvent vehicle, Dimethyl Sulphoxide (DMSO), has been investigated. Reversal with DMSO was carried out in Wistar albino rats 90 days after bilateral vas occlusion. The body weight, organ weight, sperm characteristics, fertility test and teratology, including skeletal morphology were evaluated in vas occlusion and reversal animals and in F(1) progenies to assess the functional success of the occlusion and reversal. Body weight, organ weight and the cauda epididymal sperm characteristics of vas occlusion and reversal animals and of F(1) progenies were comparable to control. Ejaculated spermatozoa in the vaginal smear showed detached head/tail, acrosomal damage, bent midpiece, bent tail and morphological aberrations in sperm head after vas occlusion, which returned to normal, 90 days after reversal. Monthly fertility test, post-injection showed 0% fertility, which improved gradually and 100% fertility was achieved 90 days after reversal. The fertility/pregnancy/implantation record and skeletal morphology of the offspring were comparable to control. The results suggest functional success and safety of vas occlusion reversal by DMSO.

Efficacy trial on the purified compounds of the seeds of Carica papaya for male contraception in albino rat.

The contraceptive efficacy and toxicological screening of the two principal compounds, MCP I and ECP I, isolated from the seeds of Carica papaya, in male albino rats at the standardized dose regimen, at 50 mg/kg b.w./day, for a period of 360 days and up to 90 days of treatment withdrawal have been reported. The body and organ weights, cauda epididymal sperm characteristics, androgen sensitive tissue biochemistry, reactive oxygen species and anti-oxidant defense system in the cauda epididymal microenvironment, histology and ultrastructure of testis and cauda epididymis, histology of seminal vesicle and prostate, toxicological investigations through routine hematology and serum clinical chemistry, sexual behaviour and fertility index have been studied. The results revealed that oral administration of MCP I and ECP I were equally effective, exhibiting complete inhibition of sperm motility following 90 days of treatment that coincided with a gradual and significant decline in cauda epididymal sperm density, percent viable spermatozoa and significant increase in sperm anomalies. Histology of testis of treated animals revealed degenerated germinal epithelium, vacuolization in Sertoli cells and proliferating germ cells and disturbances in spermatid differentiation. Spermatogonial stem cell reserves and Leydig cells appeared normal. Ultrastructure of the testis revealed vacuolization in the Sertoli cells and germ cells, loss of cytoplasmic characteristics in the Sertoli cells, nuclear degeneration and mitochondrial vacuolization in spermatocytes and spermatids. Leydig cells exhibited steroidogenic features. Cauda epididymis showed normal epithelial cell function. Absence of spermatozoa or disruption of spermatozoa clusters in the lumen were evident. Ultrastructure of cauda epididymis revealed normal secretory activity. Morphology of seminal vesicle and prostate of the treated animals were comparable to control animals. Serum testosterone, tissue biochemical and toxicological parameters remained unaffected. Fertility test revealed 100% efficacy. All the altered parameters showed sign of recovery following 90 days of treatment withdrawal. It is concluded that both MCP I and ECP I are equally effective in terms of contraceptive efficacy which is likely reversible and without adverse side effects.

Safety evaluation of long-term vas occlusion with styrene maleic anhydride and its non-invasive reversal on accessory reproductive organs in langurs.

AIM: To evaluate the safety of the long term vas occlusion with styrene maleic anhydride (SMA) and its non-invasive reversal at the level of accessory reproductive glands ARGs in langurs. METHODS: The morphology of seminal vesicle and ventral prostate was evaluated by light as well as transmission electron microscopy. Serum clinical chemistry and urine albumin were evaluated in an autoanalyzer using reagent kits. Fructose, acid phosphatase and zinc in the seminal plasma were evaluated spectrophotometrically according to the WHO manual. Serum testosterone, prostate specific antigen and sperm antibodies were evaluated by enzyme-linked immunosorbent assays (ELISA) using reagent kits and hematology was estimated according to standard procedures. RESULTS: The morphological features and secretory activity of the seminal vesicle and prostate were normal as evidenced by the presence of well-developed mitochondria, rough endoplasmic reticulum, Golgi bodies, secretory granules and normal nuclear characteristics throughout the course of investigation. Serum testosterone and prostate specific antigen remained unaltered and serum antisperm antibodies level presented negative titres. Urine albumin was nil. Total red blood corpuscles (RBC), white blood corpuscles (WBC), hemoglobin (Hb) and red cell indices, serum protein, glucose, cholesterol, creatinine, creatine kinase (CK), serum glutamate oxalate transaminase (SGOT), serum glutamate pyruvate transaminase (SGPT), lactate dehydrogenase (LDH), bilirubin, urea, triglycerides and high-density lipoprotein (HDL) did not show appreciable changes following vas occlusion and after its non-invasive reversal. Although fructose, acid phosphatase (ACP) and zinc in the seminal plasma showed a significant reduction following vas occlusion, it could not be related to the morphology of seminal vesicle and prostate. CONCLUSION: SMA vas occlusion and its non-invasive reversal do not damage the accessory reproductive organs.

Perspectives of contraceptive choices for men.

Apart from condoms and vasectomy, which have several limitations of their own, no other methods of contraception are available to men. Various chemical, hormonal, vas based and herbal contraceptives have been examined and few of them have reached the stage of clinical testing. Promising leads have been obtained from testosterone buciclate/undecanoate, alone or in combination with levonorgestrel butanoate or cyproterone acetate, RISUG, an injectable intravasal contraceptive and a few herbal products, particularly the seed products of Carica papaya. It is feasible that an ideal male contraceptive, that meets out all the essential criteria will be made available to the community in the near future.

Status of spermatogenesis and sperm parameters in langur monkeys following long-term vas occlusion with styrene maleic anhydride.

Vas occlusion by styrene maleic anhydride (SMA), trade name RISUG (one of the promising male contraceptive procedures currently in phase III clinical trials), at 60 mg/vas deferens dissolved in 120 micro L dimethyl sulphoxide (DMSO) at up to a 540-day study period caused severe oligospermia in the first 2 to 3 ejaculations and uniform azoospermia in the subsequent ejaculations without toxicity in langur monkeys. The ejaculated spermatozoa were necroasthenoteratozoospermic, suggesting instant sterility. Routine hematology and clinical chemistry parameters and the serum testosterone and sperm antibody titers remained unchanged from their pretreatment values until 540 days vas occlusion. Histology of testes revealed continued spermatogenesis throughout the study period. The stages of spermatogenesis appeared normal until 300 days of vas occlusion. At 360 days of vas occlusion, germ cells appeared in the lumen. Degeneration of seminiferous epithelium was evident in some of the tubules. Following 420 days of vas occlusion, the central portion of the testis showed regressed seminiferous tubules depicting various shapes and devoid of germ cells, which continued until 540 days of vas occlusion. Ultrastructure of the testes after 540 days of vas occlusion revealed vacuolization in the cytoplasm of Sertoli cells and degenerative features in the membranes of the spermatocytes and spermatids in the affected seminiferous tubules. The sub-cellular features of the normal tubules were similar to those of controls. The results suggest focal degeneration of seminiferous epithelium in the central portion of the testis following long-term vas occlusion with SMA.

Reversible contraception with chloroform extract of Carica papaya Linn. seeds in male rabbits.

The contraceptive efficacy and reversibility of the chloroform extract of the seeds of Carica papaya in adult male rabbits were investigated. Eighteen adult male rabbits were divided into three groups of six animals each; Group I--control, Group II--administered chloroform extract of the seeds of Carica papaya at 20 mg/animal/d for 150 d by gavage, and Group III--administered the seed extract at 50 mg/animal/d for 150 d. Body weight and organ weight, semen analysis, sperm morphology by scanning electron microscopy, semen biochemistry, histology of the testis, haematology, serum clinical biochemistry, and the fertility status of the control and the treated animals were evaluated. Body weight and the weight of the testis, epididymis, seminal vesicles, and prostate did not show appreciable changes. Sperm concentration showed a gradual decline, reached severe oligospermia (fewer than 20 million/mL) after 75 d treatment, and attained uniform azoospermia after 120 d treatment. Sperm motility and viability were severely affected after 45 d treatment and reached less than 1% after 75 d treatment. The morphology of the spermatozoa by scanning electron microscopy revealed membrane damage in the acrosome, bent midpiece, coiled tail, and detached head and tail. The levels of fructose, glycerylphosphorylcholine, acid phosphatase, and lactate dehydrogenase in the seminal plasma were unaltered. Histology of the testis revealed arrest of spermatogenesis beyond the level of spermatocytes. No toxicity was evident from the haematology and serum biochemistry parameters. The libido of the treated animals was unaffected and the fertility rate was zero. The effects were comparable in both the dose regimens (Groups II and III) and were restored to normal 45 d after withdrawal of the treatment.

Ultrastructural changes in the vas deferens of langur monkeys Presbytis entellus entellus after vas occlusion with styrene maleic anhydride and after its reversal.

Ultrastructural changes in the vas deferens of langur monkeys after 150 days of vas occlusion with styrene maleic anhydride (SMA) and after 150 days of noninvasive reversal are reported. The vas deferens of the sham-operated control animals revealed active secretory and absorptive functions. The basal cells showed prominent nucleus and sparse cytoplasmic organelles, and the principal cells characterized by oval or irregular nucleus, well developed mitochondria, Golgi bodies, rough endoplasmic reticulum, secretory granules in the Golgi area, free ribosomes, and glycogen granules in the supranuclear region suggesting secretory function. Vesicles and stereocilia in the apex region suggested absorptive functions of the vas deferens. Vas occlusion by SMA resulted in exfoliation of epithelial cells, pyknotic nuclei, and vacuolated cytoplasm virtually devoid of cytoplasmic organelles and stereocilia. After noninvasive reversal, the vas epithelium regained a state of normalcy as evidenced by prominent plasma membrane, nucleus, cytoplasmic organelles, and stereocilia. The results suggest that the exfoliation of the epithelium due to vas occlusion by SMA regains normalcy after 150 days of noninvasive reversal.

Ultrastructural changes in the spermatozoa of langur monkeys Presbytis entellus entellus after vas occlusion with styrene maleic anhydride.

Changes in the physical characteristics of semen and ultrastructure of the spermatozoa of langur monkeys after vas occlusion with styrene maleic anhydride (SMA), a polymer with pH-lowering action, are reported. Vas occlusion resulted in severe reversible hypospermia. Severe oligospermia was observed in the majority of animals (five of eight) in the first ejaculation, 30 days after vas occlusion, and in two animals in the second ejaculation, 60 days after vas occlusion. Subsequent monthly ejaculations for 5 months revealed uniform azoospermia. The voided spermatozoa were immotile and supravital staining confirmed necrospermia. Scanning electron microscopy (SEM) revealed severe coiling of tail, rupture of acrosomal envelope, and bent midpiece associated with damaged mitochondrial sheath. Observations by transmission electron microscopy (TEM) revealed vacuolization in the nucleus, membrane damage in the acrosome, loss of segmented columns, and numeric aberrations in the centriole of the neck, as well as degeneration of mitochondrial sheath and axoneme in the midpiece, and absence of outer plasma membrane in the midpiece and tail. The results indicate that the necrospermic status of the spermatozoa during initial ejaculations may offer instant sterility after vas occlusion with SMA.

Intravasal contraception with styrene maleic anhydride and its noninvasive reversal in langur monkeys (Presbytis entellus entellus).

In male langurs with azoospermia induced by vas occlusion with styrene maleic anhydride (SMA), the exploratory feasibility of azoospermia reversal by a new noninvasive reversal procedure has been assessed. Palpation, percutaneous electrical stimulation of the vas deferens, forced vibratory movement, suprapubic percussion, and per rectal digital massage of the vas deferens are the components of the multimodal noninvasive reversal procedure. The exploratory investigation reveals that a single application of the procedure leads to reversal of azoospermia. Normospermia with normal motility and viability appears after third ejaculation onwards after reversal manipulations. Ultrastructure of the spermatozoa, using scanning and transmission electron microscopy, revealed that the spermatozoa attained normalcy and sperm functional tests (i.e., hypo-osmotic swelling test, slide test for acrosome intactness, and test for sperm mitochondrial activity index) further confirmed the normalcy of the spermatozoa toward their fertilizing ability. Semen biochemistry appeared normal throughout the course of investigation. The morphology of the vas deferens, which showed exfoliation of the epithelium, was in the process of regaining normalcy after 90 days of reversal manipulations. The results suggest that noninvasive reversal technique offers the possibility of the functional azoospermia reversal within a short period of time.

Vas deferens, a site of male contraception: an overview.

The vas deferens is a site which can be exploited for male contraception without undue side effects. The only effective technique available for male contraception is vasectomy, being practiced world wide, despite that it is a permanent surgical procedure and its successful reversal is not assured. Although no-scalpel vasectomy minimizes surgical procedures, the fate of its reversal is akin to that of vasectomy. Several occlusive and non-occlusive vasal procedures which claim to be reversible without surgical intervention, possess more disadvantages than advantages. Vas occlusion with plug, 'Shug' or medical grade silicone rubber, although claimed to produce reversible azoospermia without affecting spermatogenesis, requires skilled microsurgery for their implantation and later removal. RISUG, a non-sclerotic polymer styrene maleic anhydride (SMA), could be more advantageous than vasectomy and other vas occlusive procedures in that it could be a totally non-invasive procedure by "no-scalpel injection" and "non-invasive reversal". It is claimed to offer long-term contraception without adverse side effects and also to be possible as a male spacing method by repeated vas occlusion and non-invasive reversal. The drug is currently under multicentre Phase III clinical trial.

Human sperm immobilization effect of Carica papaya seed extracts: an in vitro study.

AIM: To examine if the seed extracts of Carica papaya, which showed antispermatogenic/sperm immobilization properties in animal models, could cause human sperm immobilization in vitro. METHODS: Chloroform extract, benzene chromatographic fraction of the chloroform extract, its methanol and ethyl acetate sub-fractions and the isolated compounds from the sub-fractions i.e., ECP 1 & 2 and MCP 1 &2, of the seeds of Carica papaya were used at concentrations of 0.1%, 0.5%, 1% and 2%. Sperm motility was assessed immediately after addition of extracts and every 5 minutes thereafter for 30 minutes. RESULTS: There were dose-dependent spermicidal effects showing an instant fall in the sperm motility to less than 20% at 2% concentration. Isolated compounds ECP 1 & 2 were more effective inducing a motility of less than 10%. Many of the spermatozoa became vibratory on the spot. Total inhibition of motility was observed within 20-25 min at all concentrations of all products. Scanning and transmission electron microscopy revealed deleterious changes in the plasma membrane of the head and mid-piece of spermatozoa. Sperm viability test and the number of abnormal spermatozoa after completion of incubation suggested that the spermatozoa were infertile. The effects were spermicidal but not spermiostatic as revealed by the sperm revival test. CONCLUSION: The results reveal spermicidal activity in vitro of the seed extracts of Carica papaya.

Chloroform extract of Carica papaya seeds induces long-term reversible azoospermia in langur monkey.

AIM: To evaluate the antifertility activity of the chloroform extract of Carica papaya seeds by oral administration in langur monkey, Presbytis entellus entellus. METHODS: The chloroform extract of Carica papaya seeds, 50 mg/kg/day, was administered orally for 360 days to adult male langur monkeys. The sperm characteristics by light and electron microscopy, the sperm functional tests, the semen biochemistry, the serum testosterone level, the Leydig cell function, and the histology and ultrastructure of testis were determined to evaluate the antifertility activity and the blood biochemistry and hematology, to evaluate the toxicology. RESULTS: The extract gradually decreased the sperm concentration since days 30-60 of treatment with a total inhibition of sperm motility, a decrease in sperm viability and increase in sperm abnormality. Azoospermia was observed after day 90 of treatment and continued during the whole treatment period. Treatment withdrawal resulted in a gradual recovery in these parameters and 150 days later they reverted to nearly the pretreatment values. Morphological observation of the ejaculated sperm by light and scanning electron microscopy showed deleterious changes, particularly on the mid-piece. Sperm functional tests, viz., sperm mitochondrial activity index, acrosome intactness test and hypo-osmotic swelling test scored in the infertile range during treatment and returned to the fertile values 150 days after drug withdrawal. Histology of the testis revealed shrunken tubules, germ cell atrophy and normal Leydig cells. Ultrastructure of the testis showed vacuolization in the cytoplasm of Sertoli cells and germ cells. Loss of cytoplasmic organelles were evident in the spermatocytes and spermatids. Round spermatids showed loss of Golgi bodies, peripheral mitochondria and vacuolated cytoplasm, indicating maturational arrest. Leydig cell functional test indicated a mild inhibition of steroidogenic function. Haematology and serum biochemistry study disclosed no significant toxicological effect and the serum testosterone level was not affected. CONCLUSION: Carica papaya seed extract may selectively act on the developing germ cells, possibly mediated via Sertoli cells, leading to azoospermia.

Contraceptive evaluation and toxicological study of aqueous extract of the seeds of Carica papaya in male rabbits.

The contraceptive evaluation and toxicological effects of the aqueous extract of the seeds of Carica papaya in adult male rabbits have been reported. Thirty adult male rabbits were divided into five groups of six animals each; Group I, control; Groups II-V were administered orally with aqueous extract of the seeds of C. papaya at doses of 20, 50, 75 and 100 mg/kg per day for 150 days, respectively. The body weight, reproductive organs weight, semen analysis, semen biochemistry, toxicological profiles and the fertility status have been recorded. The aqueous extract failed to exhibit contraceptive effects at any of the dose regimens tested, contrary to the observations made in the previous studies. Unaltered toxicological profiles indicated that the drug was free of side effects. The results suggest that the failure of contraceptive effects may be due to species specificity, relative resistance of the animals to the drug or lack of potency of the extract due to factors generally affect biological activity of the plant preparations.

Ultrastructural changes induced by leaves of Azadirachta indica (Neem) in the testis of albino rats.

The present work was designed to study the effect of Azadirachta indica (Neem) powder on rat testis using the electron microscope. Male albino rats received 100 mg each A. indica leaf powder orally (by gavage). On alternate days, a second group of rats received 0.125 mg testosterone dipropionate intramuscularly. A third group received both A. indica leaf powder by gavage and testosterone dipropionate intramuscularly. Suitable controls were maintained. After autopsy, ultrastructural analysis of the testis revealed that animals treated with testosterone dipropionate showed well-developed Sertoli cells and germ cells with well-developed cytoplasmic organelles. By contrast, in A. indica-treated rats, intracellular spaces and vacuolization were observed in Sertoli cells; whereas in Leydig cells, cytoplasmic inclusions appeared diminished, and the configuration of granular endoplasmic reticulum appeared as a single unbranched tubule. In late spermatids, defects were observed in the mitochondrial sheath. The ultrastructural changes seen in the A. indica-treated group provide a clue that A. indica leaves might affect spermatogenesis through antispermatogenic and antiandrogenic properties.

Antifertility effect of Andrographis paniculata (Nees) in male albino rat.

Dry leaf powder of A. paniculata, when fed orally to male albino rats, at a dose level of 20 mg powder per day for 60 days, resulted in cessation of spermatogenesis, degenerative changes in the seminiferous tubules, regression of Leydig cells and regressive and/or degenerative changes in the epididymis, seminal vesicle, ventral prostate and coagulating gland. There was reduction in the weight and fluid content of the accessory glands. The treatment also resulted in accumulation of glycogen and cholesterol in the testis, and increased activities of lactate dehydrogenase in testis and alkaline phosphatase in testis and ventral prostate. The results suggest antispermatogenic and/or antiandrogenic effect of the plant.

Effect of Azadirachta indica leaves on testis and its recovery in albino rats.

Histological and biochemical changes in the testis of rats treated with the leaf powder of A. indica are reported. The pattern of recovery is also studied at 8, 16 and 24 day after withdrawal of the treatment. In the treated rats, a general reduction in the diameters of seminiferous tubule, nuclei of the germinal elements and a mass atrophy of the spermatogenic elements has been observed. The Leydig cells are found to be atrophic. Biochemically, a decrease in the protein content and the activity of acid phosphatase and an increase in the total free sugar, glycogen, cholesterol contents and the activities of alkaline phosphatase and lactate dehydrogenase have been observed. A gradual recovery is observed in both the histological and biochemical parameters after 8.16 and 24 day of cessation of the treatment. The result suggest a possible reversible antiandrogenic property of the leaves of A. indica in male albino rats.

Changes in epididymal structure and function of albino rat treated with Azadirachta indica leaves.

The histological and biochemical changes in the caput and cauda epididymis of albino rat treated with 20, 40 and 60 mg dry powder of the leaves of A. indica per day for 24 days are reported. In the treated rats, the height of the epithelium and the diameter of the nucleus in both the regions were reduced. The lumen of the caput was packed with lymphocytes. Biochemically, a decrease in the protein content and acid phosphatase activity and an increase in the alkaline phosphatase and lactate dehydrogenase activities were observed in both the regions. The effect was dose dependent. Further, serum testosterone concentration in the higher dose treated animals decreased significantly. The results suggest a possible antiandrogenic property of the leaves of A. indica.

Effects of Azadirachta indica leaves on the seminal vesicles and ventral prostate in albino rats.

Oral administration of 20, 40, 60, mg of dry Azadirachta indica leaf powder for 24 days resulted in decrease in the weights of seminal vesicles and ventral prostate, reduction in epithelial height, nuclear diameter and the secretory material in the lumen. Biochemically, there was a decrease in total protein, acid phosphatase activities. Seminal vesicles and ventral prostate being androgen dependent, the regressive changes histologically as well as biochemically, suggests the antiandrogenic property of the neem leaves.

Safety evaluation of long term oral treatment of methanol sub-fraction of the seeds of Carica papaya as a male contraceptive in albino rats.

ETHNOPHARMACOLOGICAL RELEVANCE: The manuscript is one of the series of attempts in authenticating scientific documentation of the seeds of Carica papaya being traditionally used for contraception. AIMS OF THE STUDY: To establish safety of the methanol sub-fraction (MSF) of the seeds of Carica papaya as a male contraceptive following long term oral treatment. MATERIALS AND METHODS: MSF was administered orally to albino rats at multiples of contraceptive dose (CD) at 50 (1x), 100 (2x), 250 (5x) and 500 (10x)mg/kg body weight daily for 52 weeks. Body weight, organs weight, morbidity, mortality, clinical chemistry, sperm analysis, histopathology and serum testosterone were evaluated to assess the safety and contraceptive efficacy. RESULTS: MSF treatment at various dose regimens, daily for 52 weeks did not show significant changes in body weight, organs weight, food and water intake and pre-terminal deaths compared to those of control animals. Sperm count and viability in 50mg/kg body weight treated animals and the weight of epididymis, seminal vesicle and prostate of all the treated animals showed significant reduction compared to control. Cauda epididymal spermatozoa of 50mg/kg body weight treated animals were immotile. Azoospermia was observed in 100, 250 and 500 mg/kg body weight treated animals. Serum clinical parameters, serum testosterone and histopathology of vital organs were comparable to those of control animals. Histology of testis revealed adverse effects on the process of spermatogenesis, while the histology of epididymis, seminal vesicles and ventral prostate showed no changes compared to control. CONCLUSION: The long term daily oral administration of MSF affects sperm parameters without adverse side effects and is clinically safe as a male contraceptive.