热暴露大鼠心肌细胞钙稳态及其调节机制的研究  

MECHANISM OF INTRACELLULAR CALCIUM HOMEOSTASIS IN HEAT-EXPOSED CARDIOMYOCYTES OF RATS

作　　者：杨晓昊[1] 李文选[1] 程素琦[1] 陈西京[1] 

机构地区：[1]天津卫生学环境医学研究所

出　　处：《生理学报》1996年第5期464-468,共5页Acta Physiologica Sinica

摘　　要：本文观察了离体成年大鼠心室肌肌质同、线粒体Ｃａ２＋－ＡＴＰ酶活性和总钙含量以及原代培养乳鼠心肌细胞４５Ｃａ摄取、活性钙调素相对含量、胞浆内游离钙浓度在不同温度热暴露４０ｍｉｎ后的变化。结果表明：热暴露后，心肌匀浆、肌质网及线粒体中的Ｃａ２＋－ＡＴＰ酶活性有所下降，心肌肌质同及线粒体中的总钙含量亦有降低趋势，心肌细胞活性钙调素相对含量显著下降，４５Ｃａ摄取量及胞浆内游离钙浓度显著升高。提示：热暴露后心肌细胞钙超载是导致机体心功能损害的重要原因之一。The activity of Ca2+-ATPase and calcium content were measured in sarcoplasmicreticulum (SR) and mitochrondria of myocardium from 40 adult female Wistar rats after exposure to 37℃, 39℃, 41℃ and 43℃ for 40 min respectively in vitro. The 45Cauptake, intracellular free Ca2+ concentration ([Ca2+ ]i) and the relatively activecalmodulin content were also observed in cultured cardiomyocytes from 120 neonatalWistar rats under the same condition of heat exposure. The results showed that (1) theactivity of Ca2+-ATPase of SR and mitochrondria of myocardium decreased after heatexposure, (2) the calcium content of SR and mitochrondria also showed a tendency ofdecrease with increase of exposure temperature, (3) the 45Ca uptake and mean [Ca2+]iincreased, whereas the calmodulin content decreased. It is suggested that disturbancesof intracellular calcium homeostasis may be responsible for cardiac functional disorderafter heat exposure.

关 键 词：热暴露 心肌细胞 钙稳态 

分 类 号：R339.52[医药卫生—人体生理学] Q494[医药卫生—基础医学]