Zalewska T, Kasai Y, Kawashima S
Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland.
Biomed Biochim Acta. 1989;48(2-3):S166-9.
The effect of hypoxia (7% oxygen in nitrogen) on Ca2+-activated protease (/u- and mCANP) in the rat brain has been studied. Hypoxia changed the intracellular distribution of CANPs without affecting the total calcium dependent proteolytic activity. The 3-fold rise of the activity of mCANP bound to synaptosomal membranes and less pronounced elevation in mitochondrial and microsomal fractions is compensated by corresponding drop of mCANP activity in cytosol. The changes of /uCANP under hypoxia were less expressed and their direction was opposite to mCANP. Additionally the susceptibility of brain membrane proteins to mCANP was tested. Our results show that proteins from the brains of animals submitted to hypoxic conditions are more susceptible to CANP than those from control animals. Thus, it is suggested that hypoxia results in some physico-chemical changes of membranes which render the membranes more sensitive to CANP.
研究了缺氧（氮气中含7%氧气）对大鼠脑中Ca2+激活蛋白酶（μ-和mCANP）的影响。缺氧改变了CANP的细胞内分布，但不影响总的钙依赖性蛋白水解活性。与突触体膜结合的mCANP活性增加了3倍，线粒体和微粒体部分的升高不太明显，这被胞质溶胶中mCANP活性的相应下降所补偿。缺氧条件下μCANP的变化较小，且其变化方向与mCANP相反。此外，还测试了脑膜蛋白对mCANP的敏感性。我们的结果表明，处于缺氧条件下动物脑内的蛋白比对照动物脑内的蛋白对CANP更敏感。因此，提示缺氧导致膜发生一些物理化学变化，使膜对CANP更敏感。
