Excitability of female rat central gray cells with medullary projections: changes produced by hypothalamic stimulation and estrogen treatment.
Excitability of female rat central gray cells with medullary projections: changes produced by hypothalamic stimulation and estrogen treatment.
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具有髓质投射的雌性大鼠中央灰细胞的兴奋性：下丘脑刺激和雌激素治疗产生的变化。
DOI：
10.1152/jn.1980.44.5.1012
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发表时间：
1980
影响因子：
2.5
通讯作者：
Pfaff,DW
中科院分区：
文献类型：
--
作者：
Sakuma,Y;Pfaff,DW
1.在乌拉坦麻醉下，用细胞外方法观察了雌激素对74个中脑中央灰质神经元兴奋性的影响。2.经雌激素处理的CG细胞的平均自发放电率（2.9 Hz）高于未经处理的卵巢切除大鼠（0.3 Hz）。在雌激素处理的制剂中，18.5%的识别细胞的放电率超过3.0 Hz，而在未处理的动物中没有发现在这个范围内。3.两种类型的正-负双相逆向峰电位区分。在一个（“快速”）中，初始正偏转在500-700微秒内完成，而在另一个（“缓慢”尖峰）中，它需要超过1 ms的时间。慢尖峰在其初始正偏转的上升阶段有一个缺口，在那里逆向传播往往被阻止。快棘波的平均逆向棘波潜伏期为6.8 ms，而慢棘波的值为14.7 ms。在缓慢的尖峰，成功的逆向尖峰入侵的体树突复合体的百分比保持恒定的很长一段时间时，引起的反应是由重复的逆向刺激在0.5 Hz。逆行传播到体树突状复合体发生更频繁地记录从雌激素处理的制剂（94.2%）比卵巢切除未处理的动物（55.7%）的缓慢尖峰。5.视前区（POA）的电刺激减少了成功的逆向传播到体树突复合体的频率。电刺激下丘脑腹内侧核（VMN）可使其增强，而电损毁POA则使其增强，电损毁VMN则使其减弱。6.因此，在CG的一些神经元的兴奋性是由雌激素促进。电刺激VMN和损毁POA的作用相似，提示这些结构可能介导雌激素样作用。对这些CG神经元的影响模式是其控制脊柱前凸行为所需的，这是雌性啮齿动物中的雌激素依赖性姿势反射。这些细胞可以调节延髓网状脊髓细胞，这反过来又控制反射。
1. Effects of estrogen on the excitability of 74 neurons in the central gray of the mesencephalon (CG) antidromically identified from the medulla were investigated extracellularly in female rats under urethan anesthesia. 2. The mean rate of spontaneous discharge of the identified CG cells was higher in estrogen-treated (2.9 Hz) than in untreated ovariectomized rats (0.3 Hz). In the estrogen-treated preparations, 18.5% of the identified cells had discharge rates exceeding 3.0 Hz, while none were found in this range in the untreated animals. 3. Two types of positive-negative biphasic antidromic spike potentials were distinguished. In one ("fast") the initial positive deflection was completed within 500-700 microseconds, while it took longer than 1 ms in the other ("slow" spikes). Slow spikes had a notch in the rising phase of their initial positive deflection, at which antidromic propagation was often blocked. Mean antidromic spike latency for the fast spikes was 6.8 ms, while the value for the slow spikes was 14.7 ms. 4. In slow spikes, the percentage of successful antidromic spike invasions into the somatodendritic complex remained constant for a long time when the response was elicited by repetitive antidromic stimuli at 0.5 Hz. Antidromic propagation into the somatodendritic complex occurred more frequently in the slow spikes recorded from estrogen-treated preparations (94.2%) than in those of ovariectomized untreated animals (55.7%). 5. Electrical stimulation of the preoptic area (POA) reduced the frequency of successful antidromic propagation into the somatodendritic complex. Stimulation of the ventromedial nucleus of the hypothalamus (VMN) increased it. Conversely, electrolytic lesion of the POA facilitated, while VMN lesion reduced antidromic spike invasion. 6. Thus, excitability of some neurons in the CG is facilitated by estrogen. Similar effects of VMN stimulation and POA lesion suggest that the estrogenic effect could be mediated by these structures. The pattern of effects on these CG neurons is that required for their control of lordosis behavior, an estrogen-dependent postural reflex in female rodents. These cells may modulate medullary reticulospinal cells, which in turn govern the reflex.