Chateau D, Plas-Roser S, Aron C
Endokrinologie. 1981 Jul;77(3):257-68.
Small ventromedial nucleus lesions were placed in 4-day cyclic female rats in order to determine whether cycle lengthening - previously observed in some females following such lesions - could result from changes in follicular growth. A slowing up in follicle development was observed in lesioned females with a 24-hour cycle lengthening as compared to those with a maintained 4-day cyclicity. Similarly, natural 5-day cyclers displayed slower follicular growth than natural 4-day cyclers. A rebound effect in follicular growth was observed on proestrus in either natural or VMN lesioned 5-day cyclers compared to either natural or VMN lesioned 4-day cyclers. Concomitantly blood FSH level appeared to be higher on proestrus morning and afternoon in 5-day than in 4-day cyclers. The pattern of LH release differed between natural 4-day and natural 5-day cyclers on proestrus at 17:00-19:00 h. LH release appeared to be delayed by one hour in VMN lesioned rats with 24 hour cycle lengthening as compared to natural 5-day cyclers. The duration of LH release in VMN-lesioned rats with a maintained 4-day cyclicity was shorter than in natural 4-day cyclers.
在4日周期的雌性大鼠中制造下丘脑腹内侧核小损伤，以确定周期延长——此前在一些此类损伤后的雌性大鼠中观察到——是否可能是卵泡生长变化所致。与维持4日周期的雌性大鼠相比，观察到损伤的雌性大鼠卵泡发育减缓，周期延长24小时。同样，自然5日周期的大鼠卵泡生长比自然4日周期的大鼠慢。与自然或下丘脑腹内侧核损伤的4日周期大鼠相比，在自然或下丘脑腹内侧核损伤的5日周期大鼠的发情前期观察到卵泡生长的反弹效应。同时，在发情前期的上午和下午，5日周期大鼠的血液促卵泡激素水平似乎高于4日周期大鼠。在发情前期17:00 - 19:00时，自然4日周期和自然5日周期大鼠的促黄体激素释放模式不同。与自然5日周期大鼠相比，下丘脑腹内侧核损伤且周期延长24小时的大鼠促黄体激素释放似乎延迟了1小时。下丘脑腹内侧核损伤且维持4日周期大鼠的促黄体激素释放持续时间比自然4日周期大鼠短。
