Jørgensen C B
J Exp Zool. 1982 Dec 30;224(3):437-43. doi: 10.1002/jez.1402240317.
The relations between nutritional state and vitellogenic growth of oocytes were studied in 87 sexually mature female toads Bufo bufo during the postbreeding season before initiation of the next annual ovarian cycle. Recruitment of small oocytes to vitellogenic growth was correlated with resumption of food uptake and the restoration of a positive energy balance in the toads that had become depleted of energy reserves during hibernation and breeding. Treatment with exogenous gonadotropin (hCG) immediately initiated vitellogenic growth, independently of the nutritional state. But the hCG-induced vitellogenic growth was faster in toads that ate more than the maintenance ration than in those that ate less. hCG also maintained rapid vitellogenic growth in toads that starved after an initial period of feeding during which vitellogenic growth had been resumed. The results support the hypothesis that the period of ovarian quiescence, which normally follows breeding in Bufo bufo, and other anurans from the northern range of distribution of the species, results from inactivation of the hypothalamic-hypophysial gonadotropic system, and that reactivation of the system depends upon reestablishment of a proper nutritional state of the organism.
在87只性成熟的雌性蟾蜍（Bufo bufo）进入下一个年度卵巢周期之前的繁殖后期，研究了营养状态与卵母细胞卵黄生成生长之间的关系。小卵母细胞向卵黄生成生长的募集与食物摄取的恢复以及蟾蜍能量平衡的恢复相关，这些蟾蜍在冬眠和繁殖期间能量储备已耗尽。外源性促性腺激素（hCG）处理可立即启动卵黄生成生长，与营养状态无关。但是，在摄入超过维持量食物的蟾蜍中，hCG诱导的卵黄生成生长比摄入较少食物的蟾蜍更快。在最初一段时间进食后恢复了卵黄生成生长的蟾蜍中，hCG也能维持快速的卵黄生成生长，即使这些蟾蜍随后饥饿。结果支持了这样的假设，即Bufo bufo以及该物种分布范围北部的其他无尾目动物在繁殖后通常出现的卵巢静止期是由于下丘脑 - 垂体促性腺系统失活所致，而该系统的重新激活取决于生物体适当营养状态的重建。
