Pompolo Sueli, Scott Christopher J, Clarke Iain J
Prince Henry's Institute of Medical Research, Clayton, Victoria 3168, Australia.
Endocrinology. 2002 Feb;143(2):544-50. doi: 10.1210/endo.143.2.8610.
gamma-Aminobutyric acid neurons in the preoptic area (POA) of the brain may regulate GnRH neurons. The level of expression of two isoforms (65 and 67) of glutamic acid decarboxylase (GAD) in the ewe brain was determined across the estrous cycle by in situ hybridization. GAD mRNA expression (cell number and silver grains/cell) was examined in the subdivisions of the bed nucleus of stria terminalis (BnST), in the diagonal band of Broca, and the POA. The number of cells expressing GAD(65) and GAD(67) mRNA did not change across the cycle. Within the rostro-dorsal BnST, the number of silver grains/cell for GAD(65) mRNA was lower in the follicular phase than the luteal phase or at estrus. In the rostro-lateral division, expression was lower in the follicular phase. In the POA, the number of silver grains/cell for GAD(65) mRNA was lower at estrus than during the luteal phase. The number of silver grains/cell for GAD(67) mRNA did not change across the estrous cycle. GAD(65) is thought to be the active enzyme during periods of high demand of GABA and our results are consistent with the GABA neurons of BnST being most active during the luteal phase of the estrous cycle.
大脑视前区（POA）中的γ-氨基丁酸能神经元可能调节促性腺激素释放激素（GnRH）神经元。通过原位杂交技术，测定了母羊大脑中谷氨酸脱羧酶（GAD）两种同工型（65和67）在整个发情周期中的表达水平。在终纹床核（BnST）的各个亚区、布罗卡斜带和视前区检测了GAD mRNA的表达（细胞数量和每个细胞的银颗粒数）。表达GAD（65）和GAD（67）mRNA的细胞数量在整个周期中没有变化。在终纹床核的 rostro - 背侧区域，GAD（65）mRNA每个细胞的银颗粒数在卵泡期低于黄体期或发情期。在rostro - 外侧区域，卵泡期的表达较低。在视前区，GAD（65）mRNA每个细胞的银颗粒数在发情期低于黄体期。GAD（67）mRNA每个细胞的银颗粒数在整个发情周期中没有变化。GAD（65）被认为是在GABA高需求时期的活性酶，我们的结果与终纹床核的GABA能神经元在发情周期的黄体期最活跃这一观点一致。
