Brain Control of the Reproductive System

本研究小组的目的是阐明脉冲发生器在下丘脑中的位置，并阐明脉冲发生器的调节机制，脉冲发生器被认为通过脉动性 LH 释放激素 (LHRH) 的释放来调节黄体生成素 (LH) 的脉动性释放。尽管幼犬持续刺激乳头，催产素仍以脉动方式释放，这一点已经得到证实。因此，寻找LHRH脉冲发生器的位置也是本课题组的目的之一。通过以下实验证明了大鼠和柴山羊的内侧基底下丘脑（MBH）中LH脉冲发生器的存在：1）大鼠下丘脑的完全传入阻滞； 2）将胎儿正中隆起（EM）移植到成年雌性大鼠中，其中搏动性LH分泌被大鼠弓状核前部的电解损伤所阻断； 3) 大鼠下丘脑的体外动脉内灌注； 4) 柴山羊弓状核的多单位活动（MUA）记录。尝试记录 LHRH 细胞将其轴突投射到 ME 的单个单位活动。然而，仅记录了少量细胞的活动，我们无法判断 LHRH 细胞本身是否产生搏动。在幼仔连续哺乳的大鼠中，间歇性地记录到视上核和室旁核中OT细胞的爆发放电。我们发现下丘脑背内侧核中的几个神经元与OT细胞同步放电。尽管这些神经元将轴突发送到视上核，但没有发现这些细胞投射到垂体后叶。因此，这些细胞有可能将乳头发出的连续脉冲转化为间歇信息，导致 OT 的脉动分泌。这些细胞与 LHRH 脉冲发生器之间的关系仍未解决。较少的

The purpose of the present research group is to elucidate the location of the pulse generator, which is thought to regulate the pulsatile release of luteinizing hormone (LH) through the pulsatile LH releasing homone (LHRH) release, in the hypothalamus and to make clear the regulatory mechanism of the pulse generator. That oxytocin is released in a pulsatile manner in spite of the continous stimulus to the teat by pups has been well established. Therefore, a search for the location of the LHRH pulse generator is also one of the purposes of this research group.The presence of the LH pulse generator in the medial basal hypothalamus (MBH) in rats and shiba goats has been demonstrated by the following experiments : 1) Complete deafferentation of the hypothalamus in the rat ; 2) Transplantation of the fetal median eminence (EM) into the adult female rat in which the pulsatile LH secretion was blocked by electrolytic lesions made in the anterior part of the arculate nucleus in rats ; 3) In vi … More tro intra-arterial perfusion of the rat's hypothalamus ; 4) Multiple unit activities (MUA) recording from the arcuate nucleus in shiba goats. An attempt was made to record the single unit activity from the LHRH cell projecting its axon to the ME.However, the activity was recorded only from a small number of cells and we can not tell whether the LHRH cells themselves generates the pulsatility. Burst discharges of OT cells in the supra optic and paraventricular nuclei were recorded intermittently in the rat suckled continously by pups.We found several neurones fired synchronously with OT cells in the dorsomedial hypothalamic nucleus. Although these neurones send axons to the supra optic nucleus, no projection of these cells to the posterior lobe of the pituitary is found. Therefore, the possibility exists that these cells transform the continuous impulse emanating from the teat to the intermittent information causing the pulsatile secretion of OT. Relationship between these cells and the LHRH pulse generator is remained unsolved. Less