Kusemiju O, Noronha C, Okanlawon A
Department of Anatomy, College of Medicine, University of Lagos, Nigeria.
Niger Postgrad Med J. 2002 Dec;9(4):205-9.
The contraceptive potential of an aqueous crude extract of the bark of Carica papaya administered orally is reported at the dose regime of 5 and 10 ml/animal/day for 4 weeks. Although the body weight or the weights of reproductive organs, kidneys, adrenals remained unaltered during the course of treatment, there was significant alteration in the histology of the testis and semen analysis when compared to the intact control group. The seminiferous tubules of rats treated with low doses of Carica papaya for 4 weeks showed no significant histological changes compared with the control. At the high dose concentration of the extract there was disorganisation in some of the seminiferous tubules with arrest of spermatogenesis beyond the level of spermatocytes. There was also widening of the lumen of the tubules. Seminal analysis showed some of the motile spermatozoa with abnormal feature in all the experimental groups. There was a dose-dependent suppression of sperm progressive forward motility which coincided with a decrease in sperm count, viability and a dose-dependent increase in percentage abnormal spermatozoa during the 14-28 days experimental period. Taken together, the present experiment showed that complete loss of fertility is attributed to decline in sperm motility and alteration in their morphology and suggest that the aqueous extracts of Carica papaya bark is safe and could serve as an effective male contraceptive in animals.
据报道，口服番木瓜树皮水粗提物具有避孕潜力，给药剂量为5和10毫升/动物/天，持续4周。尽管在治疗过程中体重、生殖器官、肾脏、肾上腺的重量未发生改变，但与完整对照组相比，睾丸组织学和精液分析有显著变化。低剂量番木瓜处理4周的大鼠生精小管与对照组相比无明显组织学变化。在提取物的高剂量浓度下，一些生精小管出现紊乱，精子发生停滞在精母细胞水平以上。小管管腔也增宽。精液分析显示，所有实验组中一些活动精子具有异常特征。在14 - 28天的实验期内，精子前向运动呈剂量依赖性抑制，同时精子数量、活力下降，异常精子百分比呈剂量依赖性增加。综上所述，本实验表明生育能力的完全丧失归因于精子活力下降及其形态改变，并表明番木瓜树皮水提取物是安全的，可作为动物有效的男性避孕药。
