心肌细胞膜脂流动性与超微结构研究

本研究应用荧光分光光度计偏振技术研究犬实验性急性心肌梗塞早期时心肌细胞膜流动性及超微结构改变的相关程度.结果表明,冠状动脉左前降支阻断后,心肌细胞膜脂流动性明显降低,阻断前为40.952±4.623,阻断1分钟为31.936±4.008.随着缺血时间延长,,心肌细胞膜脂流动性降低越明显,阻断15和120分钟时,膜脂流动性分别为27.164±4.204和26.572±3.126(与阻断前比较,P<0.05),阻断240分钟时膜脂流动性为23.374±2.604(P<0.01,与阻断前比较).而在电镜下则见心肌组织学损坏进行性加重,因此,心肌细胞膜脂流动性的降低程度与心肌缺血时间长短和损伤程度密切相关,并与心肌组织超微结构改变相一致,是反映心肌细胞缺血损伤的一个敏感指标.

A Study on the lipid fluidity of myocardial cell membrane and its ultrastructure during early ex- perimental acute myocardial infarction in dogs.

To explore the changes of lipid fluidity (LFU) of myocardial cell membrane and its ul-trastructure during early stage of acute myocardial infarction (AMI), the LFU of myocardial cell membrane was measured by. fluorescence polarization analysis in 20 open - chest dogs with the left anterior descending branch (LAD) of coronary artery occluded. The results were as follows: The LFU of myocardial cell was apparently decreased from preoccluded 40. 952 ± 4. 623 to 1 min occluded 31. 936 ± 4. 008. The LFU of myocardial cell membrane was significantly decreased with prolonged LAD occlusion, LFU = 27. 164 ± 4. 204 and 26. 572±3. 216 when occluded for 15 and 120 min (P<0. 05, compared with control), LFU = 23. 374 ±2. 604 after occluded 240 min (P<0. 01 compared with control). And in ultrastructure, the injury of myocardium tissue progressed serious with ischemical time. Thus, the degree of its decrement was correlated well with the time of myocardial ischemia and the severity of myocardial injury and the changes of myocardium tissue in ultrastructure. LFU may be an early and sensitive marker of ischemia and injury of myocardial cell.