Nilsson G E, Winberg S
Department of Zoophysiology, Uppsala University, Sweden.
Am J Physiol. 1993 Apr;264(4 Pt 2):R733-7. doi: 10.1152/ajpregu.1993.264.4.R733.
The effects of anoxia on the brain concentrations of gamma-aminobutyric acid (GABA), glutamate, aspartate, glutamine, alanine, and taurine were measured in the shore crab (Carcinus maenas) and compared with data previously obtained from anoxia-tolerant vertebrates. C. maenas was found to survive 12 h in nitrogen-bubbled water. The changes found in brain amino acid levels were strikingly similar to those seen in anoxia-tolerant vertebrates. Thus, during anoxia, the brain of C. maenas displayed considerable increases in the concentrations of GABA (2.4-fold increase after 12 h) and alanine (8-fold increase after 12 h). By contrast, the brain levels of glutamate, aspartate, and glutamine fell significantly during anoxia, whereas the taurine level remained unchanged. Because GABA is a major inhibitory neurotransmitter in arthropods (as well as in most animal phyla), it is suggested that the increased level of GABA could promote the anoxic metabolic depression displayed by C. maenas and thus prolong anoxic survival. It is also possible that the decreases in glutamate and aspartate levels could play similar roles.
在岸蟹（Carcinus maenas）中测量了缺氧对大脑中γ-氨基丁酸（GABA）、谷氨酸、天冬氨酸、谷氨酰胺、丙氨酸和牛磺酸浓度的影响，并与先前从耐缺氧脊椎动物获得的数据进行了比较。发现C. maenas能在充氮水中存活12小时。在大脑氨基酸水平上发现的变化与在耐缺氧脊椎动物中看到的变化惊人地相似。因此，在缺氧期间，C. maenas的大脑中GABA浓度（12小时后增加2.4倍）和丙氨酸浓度（12小时后增加8倍）显著增加。相比之下，缺氧期间大脑中的谷氨酸、天冬氨酸和谷氨酰胺水平显著下降，而牛磺酸水平保持不变。由于GABA是节肢动物（以及大多数动物门类）中的主要抑制性神经递质，因此有人认为GABA水平的升高可能促进C. maenas表现出的缺氧代谢抑制，从而延长缺氧存活时间。谷氨酸和天冬氨酸水平的下降也可能起到类似作用。
