Quiñones-Jenab V, Zhang C, Jenab S, Brown H E, Pfaff D W
Laboratory of Neurobiology and Behavior, Rockefeller University, New York, NY 10021, USA.
Brain Res Mol Brain Res. 1996 Jan;35(1-2):297-303. doi: 10.1016/0169-328x(95)00232-h.
Estrogen treatment increases preproenkephalin (PPE) mRNA levels in the ventromedial nucleus of the hypothalamus (VMH). Roy et al. (Brain Res., 337 (1985) 163-166) discovered that anesthesia during estrogen priming could reduce female rat sexual receptivity. In the present study we tested whether the action of estrogen to induce PPE gene expression in the VMH could be similarly affected by anesthesia. By quantitative in situ hybridization and slot-blot analysis techniques we found a 1.8-fold increase in PPE mRNA levels in the VMH after 1 hour of estrogen treatment in ovariectomized (OVX) Sprague-Dawley female rats. Anesthetizing the rats with pentobarbital for 1 h during the exposure to estrogen blocked the estrogen induction of PPE mRNA in the VMH. By way of contrast no changes in the PPE mRNA levels were observed in the caudate putamen. A similar trend was seen using chloral hydrate. It appears that neuronal activity is required for the early phase of estrogen induction of PPE mRNA levels in the VMH. This in turn could be correlated with changes in female sociosexual behaviors.
雌激素治疗可增加下丘脑腹内侧核（VMH）中前脑啡肽原（PPE）mRNA的水平。罗伊等人（《脑研究》，337（1985）163 - 166）发现，在雌激素预处理期间进行麻醉会降低雌性大鼠的性接受能力。在本研究中，我们测试了雌激素在VMH中诱导PPE基因表达的作用是否会受到麻醉的类似影响。通过定量原位杂交和狭缝印迹分析技术，我们发现，在去卵巢（OVX）的斯普拉格 - 道利雌性大鼠中，雌激素处理1小时后，VMH中PPE mRNA水平增加了1.8倍。在暴露于雌激素期间用戊巴比妥麻醉大鼠1小时，可阻断雌激素对VMH中PPE mRNA的诱导。相比之下，尾状壳核中的PPE mRNA水平未观察到变化。使用水合氯醛也出现了类似趋势。看来，神经元活动是雌激素诱导VMH中PPE mRNA水平早期阶段所必需的。这反过来可能与雌性社会性行为的变化相关。
