Germinal epithelium changes in sexually immature rabbits treated with intratesticular testosterone implants

Endocrine effects of testosterone undecanoate as a supplementary treatment to menopausal gonadotropins or tamoxifen citrate in idiopathic oligozoospermia

OBJECTIVE

To evaluate the effects of T undecanoate given as a supplementary treatment with tamoxifen citrate (TAM) or hMG on pituitary and Leydig cell function in men with idiopathic oligozoospermia.

DESIGN

A total of 48 normogonadotropic men with idiopathic oligozoospermia were allocated in to six groups (n = 8 per group) treated with placebo, 40 mg T undecanoate three times per day, 10 mg TAM two times per day, T undecanoate and TAM, 75 IU/d hMG, and T undecanoate and hMG. All groups were evaluated with standard GnRH, thyrotropin-releasing hormone, and hCG tests before and on the final day of 3 months on treatment with measurements of FSH, LH, thyroid-stimulating hormone (TSH), PRL, T, E2, 17-hydroxyprogesterone, sex hormone-binding globulin, and seminal analyses (at least twice each time).

RESULTS

Basal and stimulated concentrations and incremental FSH and LH values showed no differences among TAM or hMG and TAM + T undecanoate or hMG + T undecanoate treated groups. Basal, stimulated, and incremental values for TSH and PRL were elevated markedly during treatment in most groups in comparison to placebo. Basal, stimulated, and incremental T and E2 values were similar in active treatment groups except that higher T concentration was found in TAM + T undecanoate as compared with T undecanoate only treated men. Finally, significant improvements were noted in important seminal parameters and particularly in the functional sperm fraction of the TAM + T undecanoate group as compared with single treatment with TAM.

CONCLUSION

These results indicate that T undecanoate in combination with TAM or hMG not only had no adverse effects on pituitary and Leydig cell activity but also seemed to improve important seminal parameters and signify that androgens may be tried as a supplementary treatment to conventional regimes in idiopathic oligozoospermia.

Testicular maturation in prepubertal New Zealand white rabbits

Testicular maturation was assessed in age-matched, sexually immature (13-17-week-old) New Zealand white rabbits using end points frequently evaluated in toxicity studies: testicular weight and testicular histology. Testicular weights and testicular maturity as assessed histologically were markedly variable in sexually immature rabbits, especially at > or = 14 weeks of age. The large variation in testicular weights in immature rabbits requires that large changes in a treatment group relative to controls be present for statistical detection of testicular weight effects at commonly used significance levels. Testicular weights and testicular maturity were strongly correlated to one another, but neither weight nor maturity was strongly correlated to body weight. Thus, stratification and randomization of immature rabbits to study groups based upon body weight will not assure an absence of group differences with respect to testicular maturity. The large variation in testicular weights and maturity in 13-17-week-old rabbits warrants caution in the evaluation of testicular changes when rabbits of this age range are used in toxicity studies.

Effects of induced peripheral anosmia on gonadal maturation in prepubertal male rabbits

The effect of induced peripheral anosmia on gonadal development and maturation was investigated in sexually immature male rabbits. Furthermore, the effect of agents promoting gonadal maturation (LHRH, hMG or methyl testosterone) on testicular development was examined in anosmic rabbits. Peripheral anosmia was induced by spraying the olfactory mucosa with 5% ZnSO4 solution; its effects were evaluated after a 45-day period, corresponding to the duration of spermatogenesis. Evaluation was based on measurement of body-weight, testicular size, testicular biopsy score count (TBSC) and a standard LHRH test (0 and 30 min) involving measurement of the blood levels of FSH, LH and testosterone before and at the end of the test. Markedly lower final and incremental values were noted in anosmic, compared to intact, animals for body-weight (P less than 0.001), TBSC (P less than 0.001), FSH (P less than 0.01) and LH (P less than 0.05). On the other hand, treatment of the anosmic rabbits with 0.9% saline, resulted in lower FSH, TBSC and testicular size increments than in rabbits treated with LHRH, hMG or testosterone, while testosterone levels and body-weight increments were similar in all groups. These findings indicate that induced peripheral anosmia is probably responsible for the inadequate gonadal maturation in prepubertal anosmic male rabbits. This relationship was confirmed by the observed stimulatory effect of administration of agents activating pituitary gonadotrophin secretion or gonadal function in anosmic animals.