Sze P Y
Brain Res. 1977 Feb 11;122(1):59-69. doi: 10.1016/0006-8993(77)90662-x.
Two inbred strains of mice, C57BL/6Bg and DBA/1Bg, were compared for genetic varaition in brain L-glutamate decarboxylase (GAD) activity. Although no large difference was found between the strains in whole brain GAD activity at adult age (27--45 days postnatally), regional examination revealed a difference in GAD activity in the cerebral cortex (15% higher in DBA); subcellular examination revealed a difference in synaptosomal fraction (21% higher in DBA). When GAD activity was measured in synaptosomal fractions prepared from dissected cerebral cortex, DBA was 34% higher than C57BL. In addition, differences in GAD activity between the two strains could be observed even in the whole brain (10--15% higher in DBA) during earlier development (15--23 days postnatally). These data indicate that at adult age, genetic difference in GAD activity between the two strains exists mainly in nerve terminals of the cerebral cortex. It is postulated that the difference may be due to a genetically mediated mechanism regulating GAD in the presynaptic terminals of GABA neurons of the cerebral cortex.
比较了两种近交系小鼠C57BL/6Bg和DBA/1Bg在脑L-谷氨酸脱羧酶（GAD）活性方面的遗传变异。虽然在成年期（出生后27 - 45天），两品系全脑GAD活性未发现大的差异，但区域检查显示大脑皮质中GAD活性存在差异（DBA高15%）；亚细胞检查显示突触体部分存在差异（DBA高21%）。当测量从解剖的大脑皮质制备的突触体部分的GAD活性时，DBA比C57BL高34%。此外，在早期发育阶段（出生后15 - 23天），即使在全脑中也能观察到两品系之间GAD活性的差异（DBA高10 - 15%）。这些数据表明，在成年期，两品系之间GAD活性的遗传差异主要存在于大脑皮质的神经末梢。据推测，这种差异可能是由于一种遗传介导的机制调节大脑皮质GABA能神经元突触前末梢中的GAD。
