脾虚大鼠壁细胞Ca^(2+)/CaM-PKⅡ活性的变化及黄芪的作用

Study on the Ca^( 2+) /CaM-PKⅡ activity in gastric parietal cells in Pi-Deficiency (脾虚) rat and the effect of Huangqi Injection (黄芪注射液)

目的 :观察大黄及利血平两种脾虚模型大鼠壁细胞Ca2 + /CaM PKⅡ的活性变化及黄芪注射液对其的作用。方法 :用Lewin胃袋法、Percoll密度梯度离心分离与纯化壁细胞 ,根据Ca2 + /CaM PKⅡ活性与激活底物磷酸化量成线性关系 ,而底物磷酸化可通过掺入标记的磷酸盐反映 ,从而测定Ca2 + /CaM PKⅡ活性 (pmol/min)。 结果 :大黄、利血平脾虚大鼠胃壁细胞内Ca2 + /CaM PKⅡ活性 (pmol/min)均明显下降 ,黄芪注射液对其有明显上调作用。 结论 :脾虚证在壁细胞胃泌素受体后信号传导通路上病理表现为低下的状态 ,这一通路活性可能为健脾益气中药发挥药理作用的重要靶点之一。

Objective: To observe the activity of calcium/calmodulin dependent protein kinaseⅡ (Ca 2+ /CaM PKⅡ) of parietal cells in the Pi deficiency rats caused by Dahuang (大黄) and reserpine. The effects of Huangqi injection (黄芪注射液) on which were investigated. Methods: The parietal cells were isolated and puridied with Gastric Sac Method described by Lewin and Percoll density gradient separation. Ca 2+ /CaM PKⅡ activity is in proportion to the substrate phosphorylation, so the activity was evaluated through measured the phosphorylation of substrate which was designed to bind to phosphocellulose. Results: The Ca 2+ /CaM PKⅡ activity of parietal cells in Pi deficiency rats caused by Dahuang and reserpine decreased to 40.41±18.32 and 34.10±9.03 respectively. They were significantly lower than which in normal group (77.56±14.90, P<0.01). After the rats treated by Huangqi, the activity in two control groups increased to 64.83±15.09 and 53.15±5.83 respectively. They were significantly higher than which of the rats in model groups respectively (P<0.05). Conclusion: Intergrating this research and previous observations, some consistent results were obtained in the research of Gas R, [Ca 2+ ]i, CaM, Ca 2+ /CaM PKⅡ. A relatively affirmative conclusion was drawn. That Gas R and its signal conduction was in a lower metabolic condition is an important pathological expression in Pi deficiency rats. And Gas R and the signal conduction is one of the targets of the effects of invigorating Pi and replenishing Qi herbs.