Sperm characteristics and ultrastructure of testes of rats after long-term treatment with the methanol subfraction of Carica papaya seeds  

经番木瓜种子甲醇分馏物长期治疗后大鼠的精子特点和睾丸超微结构

作　　者：Boomi Manivannan Ruchi Mittal Shipra Goyal Abdul S. Ansari Nirmal K. Lohiya 

机构地区：[1]Department of Zoology, Centre for Advanced Studies, University of Rajasthan, Jaipur 302004, India

出　　处：《Asian Journal of Andrology》2009年第5期583-599,I0003,共18页亚洲男性学杂志（英文版）

摘　　要：The contraceptive efficacy of Carica papaya seeds after short-term evaluation has been well established. We have examined the safety and mechanism of contraception in rats after long-term treatment with the methanol subfraction （MSF） of C. papaya seeds. The test substance was administered orally to the male albino rats （n = 40） at 50 mg per kg body weight each day for 360 days. Control animals （n = 40） received olive oil as a vehicle. Recovery was assessed up to 120 days after treatment withdrawal. Sperm parameters, serum testosterone levels, fertility, histology and ultrastructure of the testis, haematology and serum clinical chemistry were evaluated to establish the safety and efficacy of the test substance. Safety of long-term treatment was evidenced by unaltered health status, organ weight, haematology and clinical chemistry, and by an increase in body weight. The mechanism of contraception was shown by reduction in nuclear and cytoplasmic volume, normal nuclear characteristics and vacuolization in the cytoplasmic organelles of the Sertoli cells, as well as nuclear degeneration in spermatocytes and spermatids indicating disturbed spermatogenesis. Leydig cells were normal. Initial effects were observed in Sertoli cells at 60 days of treatment. Spermatocytes and spermatids were affected after 120-240 days of treatment. A significant decline in sperm count and viability, total inhibition of sperm motility, increased numbers of sperm abnormalities, normal serum testosterone levels and 100% sterility were evident after 60 days of treatment. All the altered parameters, including percent fertility, were restored to control level 120 days after treatment withdrawal. It is concluded that the MSF is safe for long-term treatment and the mechanism of contraception is shown by its effect on spermatid differentiation in the testis, possibly mediated by the Sertoli cell factors.The contraceptive efficacy of Carica papaya seeds after short-term evaluation has been well established. We have examined the safety and mechanism of contraception in rats after long-term treatment with the methanol subfraction （MSF） of C. papaya seeds. The test substance was administered orally to the male albino rats （n = 40） at 50 mg per kg body weight each day for 360 days. Control animals （n = 40） received olive oil as a vehicle. Recovery was assessed up to 120 days after treatment withdrawal. Sperm parameters, serum testosterone levels, fertility, histology and ultrastructure of the testis, haematology and serum clinical chemistry were evaluated to establish the safety and efficacy of the test substance. Safety of long-term treatment was evidenced by unaltered health status, organ weight, haematology and clinical chemistry, and by an increase in body weight. The mechanism of contraception was shown by reduction in nuclear and cytoplasmic volume, normal nuclear characteristics and vacuolization in the cytoplasmic organelles of the Sertoli cells, as well as nuclear degeneration in spermatocytes and spermatids indicating disturbed spermatogenesis. Leydig cells were normal. Initial effects were observed in Sertoli cells at 60 days of treatment. Spermatocytes and spermatids were affected after 120-240 days of treatment. A significant decline in sperm count and viability, total inhibition of sperm motility, increased numbers of sperm abnormalities, normal serum testosterone levels and 100% sterility were evident after 60 days of treatment. All the altered parameters, including percent fertility, were restored to control level 120 days after treatment withdrawal. It is concluded that the MSF is safe for long-term treatment and the mechanism of contraception is shown by its effect on spermatid differentiation in the testis, possibly mediated by the Sertoli cell factors.

关 键 词：Carica papaya seeds male contraception SPERMATOZOA TESTIS ULTRASTRUCTURE 

分 类 号：R697[医药卫生—泌尿科学]