C.N.R., Institute of Neuroscience, Cagliari 09100, Italy.
Eur Neuropsychopharmacol. 2011 May;21(5):414-25. doi: 10.1016/j.euroneuro.2010.07.006. Epub 2010 Nov 10.
Social isolation of rats immediately after weaning is thought to represent an animal model of anxiety-like disorders. This mildly stressful condition reduces the cerebrocortical and plasma concentrations of 3α-hydroxy-5α-pregnan-20-one (3α,5α-TH PROG) as well as increases the sensitivity of rats to the effects of acute ethanol administration on the concentrations of this neuroactive steroid. We further investigated the effects of voluntary consumption of ethanol at concentrations increasing from 2.5 to 10% over 4 weeks of isolation. Isolated rats showed a reduced ethanol preference compared with group-housed animals. Ethanol consumption did not affect the isolation-induced down-regulation of BDNF or Arc, but it attenuated the increase in the cerebrocortical concentration of 3α,5α-TH PROG induced by foot-shock stress in both isolated and group-housed animals as well as increased the percentage of number of entries made by socially isolated rats into the open arms in the elevated plus-maze test. Ethanol consumption did not affect expression of the α₄ subunit of the GABA(A) receptor in the hippocampus of group-housed or isolated rats, whereas it up-regulated the δ subunit throughout the hippocampus under both conditions. The results suggest that low consumption of ethanol may ameliorate some negative effects of social isolation on stress sensitivity and behavior.
社交隔离大鼠断奶后被认为代表了一种焦虑样障碍的动物模型。这种轻度应激条件下减少了脑皮质和血浆浓度 3α-羟基-5α-孕烷-20-酮（3α,5α-TH PROG），以及增加了大鼠对急性乙醇的影响的敏感性的这种神经活性甾体的浓度。我们进一步研究了在 4 周的隔离期间自愿饮用浓度从 2.5 到 10%的乙醇的影响。与群居动物相比，隔离大鼠表现出较低的乙醇偏好。乙醇的消耗并没有影响分离诱导的 BDNF 或 Arc 的下调，但它减轻了由足部休克应激引起的脑皮质 3α,5α-TH PROG 浓度的增加，无论是在孤立还是群居动物中，以及增加了进入高架十字迷宫试验中开放臂的社会隔离大鼠的进入次数百分比。乙醇的消耗并没有影响 GABA(A)受体α₄亚单位在群居或隔离大鼠海马中的表达，而在这两种情况下，它都在整个海马中上调了δ亚单位。结果表明，低剂量的乙醇可能改善社交隔离对应激敏感性和行为的一些负面影响。
