Hepatic Ischemia-reperfusion Intervention Role Of The 2-phase Damage Of Rat Pancreatic Islet ¦Â-cell Secretory Function And Peripheral Tissue Insulin Sensitivity And Propofol

Part OneInfluence of the second phase injury on the secretion of pancreatic beta cells and the insulin sensitivity of peripheral tissue after hepatic ischemia reperfusion in ratsObjectiveTo study the influence of the second phase injury on the secretion of pancreatic beta cells and the insulin sensitivity of peripheral tissue after hepatic ischemia reperfusion in rats.Methods56 Sprauge-Dawley rats, weighing 230-300g, were randomly divided into ischemia/reperfusion group (I/R group) and control group(C group) with 28 each. The animals in the I/R group received 70% hepatic ischemia reperfusion injury (ischemia for 1h and 12h after reperfusion). The concentration of blood glucose and plasma insulin was determined at 12h after reperfusion. The insulin secretion index was calculated. Hyperglycemic clamp test was performed at 12h after reperfusion (n=8).ResultsThe levels of blood glucose in the I/R group were significant higher than those in control group at 12h after reperfusion (9.02±1.38 vs5.53±0.95 mmol/L, P<0.01). The concentration of plasma insulin in I/R group were significant higher than those in control group too(116.45±10.87 vs 73.65±22.87 mu/L, P <0.01). But the insulin secretion index in the I/R group was remarkably lower than that in the control group (462.80±46.28 vs 1046.54±30.21, P <0.01). And the insulin resistance index in the I/R group was obviously higher than that in the C group(47.01±10.25 vs 21.53± 6.00,P <0.05). The hyperglycemic clamp test showed that the secretion of insulin in the I/R group was higher than that in control group in the second phase of HIRI (83.17±6.01 vs 99.80±10.81 mu/L, P <0.05). Both the insulin sensitivity index and the glucose metabolism rate in the I/R group were obviously lower than those in the control group(30.97±8.11 vs 64.34±7.21, P <0.01 and 29.68±4.92 vs 53.16±3.45mg·kg^-1·min^-1, P <0.01 respectively).The glucose tolerance test shows that glucose tolerance in the I/R group was lower than that in the C group at any time point.ConclusionThe second phase injury of I/R causes significant harm to the secretion of pancreatic beta cells and the sensitivity of peripheral tissues to insulin . Part TwoEffects of propofol on the secretion of pancreatic beta cells and the insulin sensitivity after the second phase injury of hepatic ischemia reperfusion in ratsObjectiveTo observe the effects of propofol on the secretion of pancreatic beta cells and the insulin sensitivity after the second phase injury of hepatic ischemia reperfusion in rats.Methods20 Sprauge-Dawley rats were randomly divided into propofol group (P group) and ischemia/reperfusion group (I/R group) with 10 rats each. The animals received 70% hepatic ischemia reperfusion injury (ischemia for 1h and 12h after reperfusion). In the P group, propofol was administered via vena jugulars from 20 min before ischemia to 120 min after reperfusion. In the I/R group, equal volume of normal saline was infused at an equal speed. Hyperglycemia clamp test was performed in each rat at 12h after reperfusion.ResultsThe hyperglycemia test showed that the concentration of insulin in the P group was higher than that in I/R group in the second phase of HIRI (84.27±15.04 vs 69.05±13.10mmol/L , P<0.05). Both the insulin sensitivity index and the glucose metabolism rate in the P group were obviously higher than those in the I/R group(56.09±10.56 vs 29.62±7.43 mmol/L, P<0.01 and 58.31±7.69 vs 32.33±7.02 mmol/L, P<0.01 respectively).Conclusion Propofol can attenuate the decrease of insulin secretion, glucose metabolism rate and insulin sensitivity caused by the second phase injury of hepatic ischemia reperfusion.