O'Connor L H, Nock B, McEwen B S
Rockefeller University, New York, N.Y.
Neuroendocrinology. 1988 Jun;47(6):473-81. doi: 10.1159/000124958.
In vitro quantitative autoradiography and the microdissection technique of Palkovitz were used to examine the effects of estradiol-17 beta on GABAA receptors and on glutamic acid decarboxylase in discrete areas of rat brain. Under the conditions examined, estradiol did not affect glutamic acid decarboxylase activity. However, treatment with estradiol decreased GABAA receptor binding in a majority of areas that contain high levels of intracellular estradiol receptors and in a number of areas that contain few or no estradiol receptors. Within one brain area, the ventromedial nucleus of the hypothalamus, the estradiol effect was mapped and found to occur within the estradiol-sensitive ventrolateral portion and the surrounding dendritic plexus. Time- and dose-response relationships were region specific suggesting that estradiol might influence GABAA-receptor binding through multiple mechanisms. Estradiol does not appear to interact directly with GABAA receptors since addition of estradiol to the assay system did not affect binding. Our findings suggest that one way estradiol might affect neuroendocrine and other centrally mediated processes is through effects on GABAA-receptor binding.
采用体外定量放射自显影术和帕尔科维茨的显微解剖技术，研究17β-雌二醇对大鼠脑离散区域中γ-氨基丁酸A型（GABAA）受体和谷氨酸脱羧酶的影响。在所研究的条件下，雌二醇不影响谷氨酸脱羧酶活性。然而，用雌二醇处理会降低大多数含有高水平细胞内雌二醇受体区域以及一些含有少量或不含雌二醇受体区域的GABAA受体结合。在一个脑区，即下丘脑腹内侧核中，绘制了雌二醇的作用图谱，发现其作用发生在对雌二醇敏感的腹外侧部分和周围的树突丛内。时间和剂量反应关系具有区域特异性，这表明雌二醇可能通过多种机制影响GABAA受体结合。由于在测定系统中添加雌二醇不影响结合，因此雌二醇似乎不直接与GABAA受体相互作用。我们的研究结果表明，雌二醇可能影响神经内分泌和其他中枢介导过程的一种方式是通过对GABAA受体结合的影响。
