Abstract:Objective:To investigate the effect of glucagonlike peptide1(GLP1) on cytosolic free calcium ion concentration(［Ca2+］ i) in isolated rat hepatocytes after hepatectomy.
Methods :The rats were allocated randomly to two groups: The rats of group one did not undergo hepatectomy. The rats of group two had 65% liver resection. The blood specimen taken from vena cava was mensurated for glucose, insulin, glucagon, and glucagonlike peptide1（GLP1） on the first, third and fifth day after hepatectomy. The ［Ca2+］i in isolated rat hepatocytes was investigated by using fura2 fluoresence, and then, in vitro, the effect of GLP1 on the ［Ca2+］ i in hepatocytes was investigated in 2 groups.
Results:The blood glucose value in group two was significantly higher than that in group one after operation (P<0.05), especially on the first day. The plasma GLP1 value was also significantly higher than that of group one (P<0.001). The level of serum insulin was decreased obviously (P<0.001), while the value of glucagon was increased,but not significantly, which led to reduction of the ratio of insulin to glucagon. The ［Ca2+］ i in hepatocytes on the first, third and fifth day after hepatectomy was decreased slightly (P>0.05) compared with that of group one. In vitro, GLP1 produced a slightly increase in the ［Ca2+］i in hepatocytes (P>0.05).
Conclusions:After hepatectomy, in rats is associated with an obvious insulin resistance, mainly due to the level of serum insulin was obviously decreased (P<0.001), and the value of glucagon was increased, which led to reduced ratio of insulin to glucagon. GLP1 is insulinomimetic upon glucose metabolism in hepatic tissue, which acting through specific receptors is not associated to ［Ca2+］ i increase.