Buniatian G K, Egian V B, Turshian G A, Akopian G E, Safrazian S S
Vopr Biokhim Mozga. 1974;9:17-24.
Glutaminsynthetase activity has been determined in microsomal and soluble fractions of brain and liver of normal and alloxan diabetic rats and glutaminase activity in homogenates and mitochondrial fractions. The results obtained indicate that in brain of diabetic animals glutaminesynthetase activity of microsomal fractions is changed very slightly while that of the soluble fraction is marked reduced. In liver tissue enzyme activity is significantly decreased in both microsomal and soluble fractions. In homogenates of brain tissue of diabetic animals glutaminase does not differ markedly from that of control animals both in the presence and absence of activators (phosphate, aspartate, bicarbonate). In homogenates of liver, in the absence of activators, glutaminase activity is greater in diabetic animals than in controls, it is not much changed in the presence of phosphate and decreases in the presence of bicarbonate and aspartate. In diabetic animals, in the presence of phosphate, glutaminase activity of brain mitochondrial fractions increases while that of liver mitochondrial fractions does not change. It is interesting to note that in the absence of activators glutaminase activity is absent in both brain and liver mitochondria while it is quite high in homogenates.
已测定正常大鼠和四氧嘧啶糖尿病大鼠脑和肝脏微粒体及可溶性部分中的谷氨酰胺合成酶活性，以及匀浆和线粒体部分中的谷氨酰胺酶活性。所得结果表明，在糖尿病动物的脑中，微粒体部分的谷氨酰胺合成酶活性变化很小，而可溶性部分的活性则显著降低。在肝脏组织中，微粒体和可溶性部分的酶活性均显著降低。在糖尿病动物脑组织的匀浆中，无论有无激活剂（磷酸盐、天冬氨酸、碳酸氢盐），谷氨酰胺酶与对照动物均无明显差异。在肝脏匀浆中，无激活剂时，糖尿病动物的谷氨酰胺酶活性高于对照动物，有磷酸盐时变化不大，有碳酸氢盐和天冬氨酸时则降低。在糖尿病动物中，有磷酸盐时，脑线粒体部分的谷氨酰胺酶活性增加，而肝脏线粒体部分的则不变。有趣的是，无激活剂时，脑和肝脏线粒体中均无谷氨酰胺酶活性，而在匀浆中则相当高。
