Study on the central mechanism for gonadotropin secretion in the female rat by brain transplantation technique.

1.用于在脑中移植儿茶酚胺神经元的方法：蓝斑内的神经组织包括A-6群去甲肾上腺素（NA）神经元（对于富含NA的移植物）或A-10组黑质中的多巴胺（DA）-神经元（对于富含DA的移植物）分别从从新生大鼠的髓质或中脑解剖的冠状切片中冲出，用金属套管，并立体定位在骑自行车大鼠的视前区水平的第三脑室中。Falck-Hillarp荧光法证实存活移植物中存在儿茶酚神经元.在第三脑室中植入了儿茶酚胺神经元的雌性大鼠的生殖功能：植入了存活的富含NA神经元的移植物的雌性大鼠经常表现出发情期延长，表明排卵严重受损。然而，卵巢切除术后，他们表现出脉冲式分泌LH的幅度非常大。DA神经元丰富的移植 关于我们 维持动情周期不变，也不改变去卵巢后LH的脉冲式分泌。结果提示，视前区富含NA神经元的移植物在一定程度上抑制了正常大鼠的促性腺激素分泌，而在去卵巢大鼠则促进了促性腺激素分泌.第三脑室儿茶酚胺神经元移植大鼠的血压：NA-神经元或DA-神经元移植大鼠均表现出持续性低血压。对盐负荷引起的高血压也有降压作用。雌孕激素对雌性新生大鼠视交叉上核脑室植入后促性腺激素分泌的影响：视交叉上核被认为是雌孕激素对雌性大鼠促性腺激素分泌起正反馈作用的关键部位。将这种神经组织移植到雄性脑中不能有效诱导LH峰，但能诱导FSH分泌。少

1. Method for transplantation of catecholamine-neuron in the brain: The neural tissue including A-6 group noradrenaline (NA)-neurons in the locus coeruleus (for NA-rich transplant) or A-10 group doapmine (DA)-neurons in the substantia nigra (for DA-rich transplant) was punched out of the coronal slice dissected from the medulla or midbrain of newborn rats, respectively, with a metal cannula and was stereotaxically positioned in the third ventricle at the level of the preoptic region of cycling rats. Surviving transplant was confirmed to have catecholaine neurons in the Falck-Hillarp fluorescence method.2. Reproductive function of the female rats with catecholamine-neuron transplants in the third ventricle: The female rat that had surviving NA-neuron rich transplant frequently showed prolongation of estrus, indicating that ovulation was severely impaired. However, after ovariectomy, they showed a pulsatile secretion of LH with a remarkably large amplitude. The DA-neuron rich transplants … More sustained the estrous cycle unchanged, and did not change pulsatile secretion of LH after ovariectomy, too. The results suggested that the NA-neurons rich transplants at the preoptic region somehow inhibited gonadotropin secretion in the intact rat, whereas they facilitated it in ovariectomized rats.3. Blood pressure of the rats with catecholamine-neuron transplant in the third ventricle: The rats with either transplant, NA-neurone ro DA-neuron, showed a long lasting hypotension. The hypotensive effect was exerted even on the hypertension produced by salt-loading.4. Effect of estrogen-progesterone treatment on the gonadotropin secretion in the gonadectomized male rat with the ventricular implantation of the preoptic suprachiasmatic nucleus from the female newborn: The preoptic suprachiasmatic nucleus has been considered as the key locus for positive feedback action of progesterone on gonadotropin secretion in the female rat. Transplantation of such a neural tissue in the male brain was not effective to induce LH surge, while FSH secretion was induced. Less