Effect of Qingyitang on activity of intracellular Ca^(2+)-Mg^(2+)-ATPase in rats with acute pancreatitis

AIM: To study the change of intracellular calcium-magnesium ATPase (Ca^2+-Mg^2+-ATPase) activity in pancreas, liver and kidney tissues of rats with acute pancreatitis (AP), and to investigate the effects of Qingyitang (QYT) (Decoction for clearing the pancreas) and tetrandrine (Tet) and vitamin E(VitE) on the activity of Ca^2+-Mg^2+-ATPase. METHODS: One hundred and five Sprague-Dawley rats were randomly divided into: normal control group, AP group,treatment group with QYT (1 ml/100 g) or Tet (0.4 ml/100 g) or VitE (100 mg/kg). AP model was prepared by a retrograde injection of sodium taurocholate into the pancreatic duct. Tissues of pancreas, liver and kidney of the animals were taken at 1 h, 5 h, 10 h respectively afer AP induction, and the activity of Ca^2+-Mg^2+-ATPase was studied using enzymehistochemistry staining. Meanwhile, the expression of Ca^2^+-Mg^2+-ATPase of the tissues was studied by RT-PCR. RESULTS: The results showed that the positive rate of Ca^2+-Mg^2+-ATPase in AP group (8.3%, 25%, 29.2%) was lower than that in normal control group (100%) in all tissues(P<0.01), the positive rate of Ca^2+-Mg^2+-ATPase in treatment group with QYT (58.3%, 83.3%, 83.3%), Tet (50.0%,70.8%, 75.0%) and VitE (54.2%, 75.0%, 79.2%) was higher than that in AP group (8.3%, 25.0%, 29.2%) in all tissues(P<0.01). RT-PCR results demonstrated that in treatment groups Ca^2+-Mg^2+-ATPase gene expression in pancreas tissue was higher than that in AP group at the observing time points, and the expression at 5 h was higher than that at 1 h. The expression of Ca^2+-Mg^2+-ATPase in liver tissue was positive, but without significant difference between different groups. CONCLUSION: The activity and expression of intracellular Ca^2+-Mg^2+-ATPase decreased in rats with AP, suggesting that Ca^2+-Mg^2+-ATPase may contribute to the occurrence and development of cellular calcium overload in AP. QYT, Tet and VitE can increase the activity and expression of Ca^2+-Mg^2+-ATPase and may relieve intracellular calcium overload to protect the tissue and cells from injuries.

A Linear Time Algorithm for the Minimum-weight Feedback Vertex Set Problem in Series-parallel Graphs

A feedback vertex set is a subset of vertices in a graph, whose deletion from the graph makes the resulting graph acyclic. In this paper, we study the minimum-weight feedback vertex set problem in series-parallel graphs and present a linear-time exact algorithm to solve it.