川芎嗪对心肌细胞核钙转运功能异常的保护

目的: 观察异丙肾上腺素(ISO) 致大鼠心肌缺血损伤时心肌细胞核钙转运功能的变化及川芎嗪对其影响。 方法: Wistar 大鼠皮下注射 5 mg·kg^-1 ISO 液, 造成心肌缺血损伤模型。超速离心分离纯化心肌细胞核。 酶学方法鉴定核纯度和测定核膜Ca²⁺-ATP 酶活性, 同位素法观测核钙的摄取。 结果: 与正常对照组比较, 心肌缺血组(实验组) 心肌细胞核膜 Ca²⁺ 依赖性ATP 酶活性降低 18.1%(P<0.05), ⁴⁵Ca²⁺ 摄取效率也显著降低, 其最大反应速度(V_max ) 降低 54.6%, 细胞核 Ca²⁺ 依赖性ATP 酶的最大反应速度(V_max ) 降低 33.0%(P<0.05), 平衡常数(K_m ) 降低 42.8%(P<0.01);川芎嗪保护组心肌细胞核 Ca²⁺-ATP 酶活性及核 ⁴⁵Ca²⁺ 摄取与正常对照组比较均未见显著性改变。结论: 川芎嗪对 ISO致大鼠心肌缺血损伤时心肌细胞核钙转运功能降低有保护作用。

Effects of liqustraxin on dysfunction of myocardial nuclear calcium trans-port

AIM: To observe the dysfunciton of my-ocardial nuclear calcium transport in rat myocardial injury and the effects of liqustraxin on it.METHODS: The model of myocardial damage was induced by subcutaneous injection of isoproterenol (ISO, 5 mg·kg^-1 ·d^-1 ).My-ocardial nuclei were purified with sucrose density centrifu-gation and identified zymologically.The activity of Ca²⁺-ATPase was measured zymologically and calcium uptake was assayed with ⁴⁵Ca²⁺ isotope.RESULTS: Compared with the control, the Ca²⁺-ATPase activity of myocardial nuclear membrane in ischemia group(exprimental) was decreased by 18.1%(P<0.05), the nuclear ⁴⁵Ca²⁺ up-take was significantly decreased and V_max value was low-ered by 54.6%.V_max and K_m of ATPase activity de-creased by about 33.0%(P<0.05) and 42.8%(P< 0.01) respectively.Compared with the control, Ca²⁺-ATPase activity and 45 Ca²⁺ uptake in the myocardial nu-clei of the liqustraxin group showed no significant change.CONCLUSION: Liqustraxin has notable protective ef-fects on dysfunction of nuclear calcium transport in rat myocardium.