Damron D S, Dorman R V
Dept. Biological Sciences, Kent State University, OH 44242.
Mol Chem Neuropathol. 1990 Jun;12(3):177-90. doi: 10.1007/BF03159943.
Cerebral minces were used to investigate the role of calcium influx on trauma-induced alterations of brain lipid metabolism. Cerebral phospholipids, nonpolar lipids, and free fatty acids were radiolabeled in vivo with [3H]arachidonic acid. Tissue incubation stimulated the time-dependent catabolism of choline and inositol glycerophospholipids, and resulted in the accumulation of [3H]free fatty acids. These effects were attenuated in Ca2(+)-free incubations, and when EGTA or verapamil were present. The inhibition of calcium influx also reduced the labeling of diglycerides, whereas ethanolamine and serine glycerophospholipids were not affected by incubation or treatments. Replacing Ca2+ with other cations also attenuated the incubation-dependent alterations in lipid metabolism. However, only cadmium was able to compete with calcium and reduce the accumulation of [3H]free fatty acids. It appeared that about half of the observed phospholipid catabolism was dependent on Ca2+ influx and that at least 80% of the [3H]free fatty acid accumulation required calcium.
使用脑碎块研究钙内流对创伤诱导的脑脂质代谢改变的作用。脑磷脂、非极性脂质和游离脂肪酸在体内用[3H]花生四烯酸进行放射性标记。组织孵育刺激了胆碱和肌醇甘油磷脂的时间依赖性分解代谢，并导致[3H]游离脂肪酸的积累。在无Ca2+的孵育中以及存在EGTA或维拉帕米时，这些效应减弱。钙内流的抑制也减少了甘油二酯的标记，而乙醇胺和丝氨酸甘油磷脂不受孵育或处理的影响。用其他阳离子替代Ca2+也减弱了脂质代谢中依赖孵育的改变。然而，只有镉能够与钙竞争并减少[3H]游离脂肪酸的积累。似乎观察到的磷脂分解代谢中约一半依赖于Ca2+内流，并且至少80%的[3H]游离脂肪酸积累需要钙。
