| Objective To explore the influence of glucagon on the cGMP signal pathyways involved in insulinsecretion and the cell viability of MIN6cell treated with the different concentrtons of glucagon(Glg) andglucose(Glu).Further reveal insulin secretion mechanism to provide a new direction to the treatment ofdiabetes.Methods MIN6cells were treated with different concentrations of glucose(2.8mmol/l-lowGlu,16.7mmol/l-high Glu)and glucagon(100ng/l-lowGlg,500ng/l-middle Glg,1000ng/l-high Glg).Eachgroup intracellular cGMP content and insulin secretion were measured by enzyme–linked immuneassay.Meanwhile the cell viaility of different groups were measured by MTT. The experimental data wereanalyzed by SPSS17.0statistical software.Results The cGMP levels of MIN6cell stimulated by different concentrations of glucagon and glucose:In glucose treatment groups,high glucose group was significantly higher than that of low Glu and no Glugroups(P<0.001);In only glucagon treatment groups,high Glg group was significantly lower than that ofno Glg groups (P<0.05);In low glucose groups,high Glg group was significantly lower than that of no Glggroup(P<0.01),middle Glg group was significantly lower than that of no Glg group (P<0.05);In highglucose groups, high Glg group was significantly lower than that of no Glg group (P<0.001), middle Glggroup was significantly lower than that of none Glg group (P<0.01). The insulin secretion levels of MIN6cell stimulated by different concentrations of glucagon and glucose, in only glucose treatment groups, highglucose group was significantly higher than that of low Glu and no Glu groups (P<0.001,P<0.05); In onlyglucagon treatment groups, high Glg group was significantly higher than that of low Glg (P<0.001);In lowglucose groups, high Glg group was significantly higher than that of low Glg (P<0.001),middle Glg groupwas significantly higher than of low Glg group(P<0.001); In high glucose groups,high Glg group wassignificantly higher than that of low Glg group (P<0.001),middle Glg was significantly higher than that oflow Glg group (P<0.001).The cell proliferation viability of groups measurement results showed: therewere no significantly different in2.8mmol/l glucose groups(P>0.05); In5.6mmol/l glucose groups, the cellproliferation viability of groups (high Glg,middle Glg, low Glg) were significantly higher than that of onlyglucose group (P<0.05, P<0.01, P<0.001); In16.7mmol/l glucose groups, the cell proliferation viability ofhigh Glg group was significantly higher than that of only glucose group (P<0.001). ConclusionsGlucagon could increase the insulin secretion of MIN6cell through downregulating the cGMP level ofMIN6cell meanwhile promoting the viability of MIN6cell. |
