Maker H S, Weiss C, Weissbarth S, Silides D J, Whetsell W
Ann Neurol. 1981 Oct;10(4):377-83. doi: 10.1002/ana.410100410.
Interpretation of biochemical measurements in the human brain after death is complicated by a variety of premortem, perimortem, and postmortem factors. The activity of glutamic acid decarboxylase (GAD) in particular has been found to vary considerably among human brains. In contrast to neurotransmitter-associated enzymes, metabolic enzymes are present in all brain cells and should not be specifically lost by patterned neuronal cell loss such as that which occurs in Parkinson disease. We compared the activity of GAD to that of the metabolic enzymes creatine kinase (CK), adenylate kinase, hexokinase, beta-glucuronidase, and malate, lactate, glucose-6-phosphate, and isocitrate dehydrogenases in 24 regions of six human brains. Of the metabolic enzymes, only CK showed a 5-fold variation approaching that of GAD. Like GAD, CK activity was stable postmortem, but its activity was apparently inversely related to the severity and duration of the preterminal illness. CK may be a useful marker of agonal deterioration.
死后对人类大脑进行生化测量的解读会受到各种生前、濒死期和死后因素的影响。特别是，已发现谷氨酸脱羧酶（GAD）的活性在人类大脑中差异很大。与神经递质相关酶不同，代谢酶存在于所有脑细胞中，不应因如帕金森病中发生的那种有规律的神经元细胞丢失而特异性丧失。我们比较了6个人类大脑24个区域中GAD与代谢酶肌酸激酶（CK）、腺苷酸激酶、己糖激酶、β-葡萄糖醛酸酶以及苹果酸、乳酸、葡萄糖-6-磷酸和异柠檬酸脱氢酶的活性。在这些代谢酶中，只有CK的活性变化达5倍，接近GAD的变化程度。与GAD一样，CK活性在死后是稳定的，但其活性显然与临终前疾病的严重程度和持续时间呈负相关。CK可能是濒死期恶化的一个有用标志物。
