Zhao Meirong, Liu Ming, Li Dong, Wan Xinrong, Hinds Lyn A, Wang Yanling, Zhang Zhibin
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China CSIRO Entomology, Canberra, Australian Capital Territory, Australia.
Integr Zool. 2007 Dec;2(4):260-8. doi: 10.1111/j.1749-4877.2007.00059.x.
The combination of levonorgestrel and quinestrol (EP-1) has been shown to have anti-fertility effects on several wild rodents, but the mechanism underlying these effects is poorly understood. We investigated the effects of EP-1 and each of its components, levonorgestrel (P) and quinestrol (E), on the fertility of Brandt's voles (Lasiopodomys brandtii) by using a gastric gavage method. The doses for EP-1, E and P were 1, 0.34 and 0.66 mg/kg body weight, respectively. Male voles (n = 98) were treated daily for 5 or 14 days, then the testes and epididymides were collected, weighed and examined histologically at 30 (D30), 60 (D60) or 90 (D90) days after the end of treatment. Four males were allowed to mate with normal females at D90. Female voles (n = 75) were treated for 3 days and a further 3 days after a 7-day interval. The uteri and ovaries were weighed and examined histologically at 15 (D15), 30 (D30) or 75 (D75) days after the end of treatment. Each of three females were mated with fertile males at D30 and D75, respectively. Our results indicated that quinestrol (E) significantly decreased the sperm numbers in the testes as well as the weight of the testes and epididymides, with both of these tissues showing obvious structural abnormalities, and significantly reduced the litter size and the pup weight for females mated with males of the E treatment group. For female voles, treatment with E, P or EP-1 resulted in no marked influence on the fertility status. These data indicate that quinestrol (E) alone has a significant anti-fertility effect on male Brandt's voles, but is ineffective in combination with levonorgestrel (P).
左炔诺孕酮与炔雌醚组合制剂（EP - 1）已被证明对多种野生啮齿动物具有抗生育作用，但其作用机制尚不清楚。我们采用灌胃法研究了EP - 1及其各组分左炔诺孕酮（P）和炔雌醚（E）对布氏田鼠（Lasiopodomys brandtii）生育力的影响。EP - 1、E和P的剂量分别为1、0.34和0.66毫克/千克体重。雄性田鼠（n = 98）每天接受治疗，持续5天或14天，然后在治疗结束后的30天（D30）、60天（D60）或90天（D90）收集睾丸和附睾，称重并进行组织学检查。在D90时，让4只雄性田鼠与正常雌性田鼠交配。雌性田鼠（n = 75）接受3天治疗，并在间隔7天后再接受3天治疗。在治疗结束后的15天（D15）、30天（D30）或75天（D75）对子宫和卵巢进行称重并进行组织学检查。分别在D30和D75时，让3只雌性田鼠与可育雄性田鼠交配。我们的结果表明，炔雌醚（E）显著降低了睾丸中的精子数量以及睾丸和附睾的重量，这两个组织均表现出明显的结构异常，并且显著降低了与E治疗组雄性田鼠交配的雌性田鼠的窝仔数和幼仔体重。对于雌性田鼠，E、P或EP - 1治疗对生育状况没有显著影响。这些数据表明，单独使用炔雌醚（E）对雄性布氏田鼠具有显著抗生育作用，但与左炔诺孕酮（P）联合使用时无效。
