Price J M, Sutton E T, Hellermann A, Thomas T
Department of Physiology and Biophysics, University of South Florida, Tampa, USA.
Neurol Res. 1997 Oct;19(5):534-8. doi: 10.1080/01616412.1997.11740853.
beta-Amyloid toxicity plays a central role in the pathology of Alzheimer's disease. Contraction and relaxation responses of pressurized rat posterior cerebral artery were studied before and after in vitro exposure to beta-amyloid. The peptide-induced characteristic features of endothelial dysfunction including enhanced vasoconstriction with serotonin and diminished relaxation to endothelium-dependent vasodilators acetylcholine and bradykinin. Response to the endothelium-independent vasodilator nitroprusside was not affected by beta-Amyloid. beta-amyloid inhibition of acetylcholine-induced vasodilation was prevented by the oxygen radical scavenging enzyme superoxide dismutase. Endothelial destruction and the protective effect of superoxide dismutase was verified by electron microscopy. The results suggest that beta-amyloid peptide produces endothelial dysfunction in cerebral microvessels through reactive oxygen species.
β-淀粉样蛋白毒性在阿尔茨海默病的病理过程中起核心作用。研究了体外暴露于β-淀粉样蛋白前后大鼠大脑后动脉加压后的收缩和舒张反应。该肽诱导的内皮功能障碍的特征包括对血清素的血管收缩增强以及对内皮依赖性血管舒张剂乙酰胆碱和缓激肽的舒张减弱。对非内皮依赖性血管舒张剂硝普钠的反应不受β-淀粉样蛋白的影响。氧自由基清除酶超氧化物歧化酶可预防β-淀粉样蛋白对乙酰胆碱诱导的血管舒张的抑制作用。通过电子显微镜证实了内皮破坏和超氧化物歧化酶的保护作用。结果表明，β-淀粉样蛋白肽通过活性氧导致脑微血管内皮功能障碍。
