Spermatogenesis in rat: effect of L-tryptophan loading

Maternal treatment with fluoxetine promotes testicular alteration in male rat pups

Fluoxetine (FLX) is a selective serotonin reuptake inhibitor (SSRI) antidepressant commonly prescribed during pregnancy and lactation. Pre- and post-partum depression, as well as SSRI treatment during these periods, may change maternal care, interfering with offspring development. Moreover, it is known that SSRIs may alter testes structure and function in offspring. The present study investigated the effects of maternal FLX exposure on maternal behaviour and testes function in offspring. Female Wistar rats were treated with 7.5mgkg-1 FLX or tap water (control group) by gavage from the Day 1 of pregnancy until 21 days after birth (postnatal Day (PND) 21). Maternal behaviour was evaluated and morphofunctional analyses of offspring testes were conducted on PND 21 and 50. There were no significant differences between the FLX-treated and control groups regarding maternal behaviour. Nor did maternal treatment with FLX have any effect on bodyweight gain, anogenital distance, day of preputial separation, testis weight and the gonadosomatic index in male offspring. However, there was a decreased number of Sertoli cells at both PND 21 and 50 in FLX-exposed male offspring. The findings of the present study demonstrate that maternal exposure to FLX can impair testicular function in weanling and pubertal animals.

Could maternal exposure to the antidepressants fluoxetine and St. John's Wort induce long-term reproductive effects on male rats?

Based on the limited number of studies that have investigated the adverse effects of maternal treatment with antidepressants on the development of male descendents, this study was carried out in rat in order to evaluate if maternal exposure to fluoxetine (FLX) or St. John's Wort (SJW) could disrupt the development of male offspring. The dams were treated daily, by gavage, with 7.5 mg/kg of FLX or 100 mg/kg SJW during pregnancy and lactation. The reproductive and behavior parameters were analyzed in male pups. Results showed decreases in the weight of the full seminal vesicle and in the number of spermatozoa. Moreover, FLX-exposed pups presented reduced seminiferous epithelium height and diameter of seminiferous tubules. The present study shows that maternal exposure to FLX, but not SJW could interfere on reproductive parameters in adult male rats.

The effect of amantadine on clomipramine induced sexual dysfunction in male rats

OBJECTIVE

Several studies have reported that Clomipramine has the ability to suppress male rat sexual behavior. Literature indicates that the activation of brain D(2) receptors causes facilitation of penile erection, and a number of reports have indicated dopamine's involvement in sexual function. Hence this study was undertaken to investigate the effect of Amantadine, a dopamine agonists on the Clomipramine induced sexual dysfunction.

METHODS

The study subjects involved a total of 48 males and 48 females, 4 months old Sprague-Dawley albino rats, all housed in a group of six males and females separately in plexi glass cages in an acclimatized colony room (25±0.5(0)C) maintained on a 12/12 hr light/dark cycle. The male rats were randomly divided into four groups of 12 male rats each. Group I served as controls. Group II, III, and IV were treated with Amantadine (9 mg/kg body weight, p.o) 30 min, prior to the treatment with 13.5 mg/kg, 27 mg/Kg and 54 mg/Kg bodyweight p.o of Clomipramine respectively for 60 days. The control group received vehicle 1 ml / kg p.o. The sexual behavior of the male rats was observed to determine the following parameters: mount latency, intromission latency, ejaculation latency, post ejaculatory pause, and intromission frequency. As well as the sexual behavior; serum testosterone and histopathology of the testes were also investigated in this study.

RESULTS

The results indicate that Amantadine in all aspects failed to antagonize Clomipramine induced sexual dysfunction in male rats. Even the sexual competence of male rats treated with ½ therapeutic dose (TD) of Clomipramine failed to regain their sexual competence in the presence of Amantadine. Testicular damage and decline in testosterone levels continued in the presence of Amantadine.

CONCLUSION

Overall, the results suggest that Amantadine could not be a safe antidote to antagonize Clomipramine induced sexual dysfunction.

Spermatogenesis of rat: effect of central norepinephrine synthesis inhibition by diethyldithiocarbamate

Spermatogenesis and steroidogenesis of male Wistar rats under the influence of a decreased central NE level was studied. Inhibition of NE synthesis was produced by chronic injection (7 days) of DDC, a Dopamine hydroxylase blocker, which decreased brain NE, increased brain DA without significantly affecting brain 5-HT. Rats were sacrificed on the day after cessation of treatment (8th day) and after an interval of 13 days following the cessation of treatment (21st day). The time interval of 13 days is equivalent to one cycle of the seminiferous epithelium in Wistar strain rats. A degenerative change (reduced spermatid count) in the spermatogenic pattern at stage-VII of the cycle of the seminiferous epithelium was observed in the rats sacrificed on the 8th day, the degeneration being much greater in the rats sacrificed on the 21st day. Rats sacrificed on the day after cessation of DDC treatment revealed an inhibition of plasma testosterone level. Such change was not observed in the rats sacrificed after the interval of 13 days following DDC treatment. Human chorionic gonadotropin supplementation in the rats sacrificed on the 21st day partially restored the spermatogenesis towards the vehicle treated control. The inhibition of spermatogenesis and steroidogenesis reflects a decrease in the pituitary gonadotropin secretion under the influence of a decreased NE synthesis in brain, following chronic treatment of DDC.

Brain 5-hydroxytryptamine and plasma testosterone in L-tryptophan treated rats

Loading of L-tryptophan for 7 and 21 days increased brain 5-hydroxytryptamine (5-HT) level which was associated with decreased plasma testosterone level. Human chorionic gonadotropin (HCG) administration in L-tryptophan treated rats for 21 days increased the plasma testosterone level in spite of increased brain 5-HT level. These results suggest that brain 5-HT exerts an inhibitory influence on testicular steroidogenesis by modulating the gonadotropin-releasing-factor (GnRH) release and thence pituitary gonadotropins.