Protection of L－arginine against lysophosphatidy lcholine－inducedmy ocardi alinjury inisolated ratheart

在离体大鼠心脏观察了Ｌ－精氨酸对溶血性磷脂酰胆碱（ＬＰＣ）损伤心肌作用的影响．ＬＰＣ（５μｍｏｌ·Ｌ－１）引起心率减慢，冠脉流量减少，心脏功能降低（ＬＶＰ和ＬＶｄｐ／ｄｔｍａｘ下降）及肌酸激酶（ＣＰＫ）释放增加．３０μｍｏｌ·Ｌ－１Ｌ－精氨酸能促进心率恢复，增加冠脉流量和改善心脏功能，但仅ＬＶｄＰ／ｄｔｍａｘ恢复显示统计学差异；３００μｍｏｌ·Ｌ－１Ｌ－精氨酸能显著改善心脏功能，促进心率和冠脉流量的恢复，减少ＣＰＫ释放．结果提示：Ｌ－精氨酸对ＬＰＣ所致心肌损伤具有一定的保护作用．

Protection of L-arginine against lysophosphatidylcholine- induced myocardial injury in isolated rat heart 1

The effect of L-arginine (Arg) on lysophosphatidylcholine (LPC)-induced myocardial injury was tested in perfused rat hearts. LPC (5 μmol·L -1 ) caused a decrease in heart rate (HR), coronary flow (CF), and cardiac function (LVP and LV dp/dt max ) as well as an increase in release of creatine phosphate kinase (CPK). Arg 30 μmol·L -1 attenuated the reduction of HR, CF and cardiac function induced by LPC, but there was significant difference only in the value of LV dp/dt max , while Arg 300 μmol·L -1 significantly improved cardiac function and increased HR and CF. Arg 30 and 300 μmol·L -1 both decreased CPK release evoked by LPC. These results suggest that Arg may protect isolated rat heart against myocardial damages evoked by LPC.