Effect of insulin and gliclazide on glucose utilization by a perfused intestine-pancreas preparation isolated from diabetic and non-diabetic rats

The effect of insulin (40 U/ml) and gliclazide (200 g/ml) on intestinal glucose metabolism was investigated by using an in vitro perfuse intestine-pancreas preparation isolated from normal or streptozotocin-diabetic rats. Glucose, lactate and alanine were measured enzymatically in the portal effluent. The glucose retained by the perfused preparation was reduced (P<0.05) in diabetic versus control rats. The portal lactate levels were not modified, but alanine portal levels were increased (P<0.05) in diabetic versus control rats. In the diabetic rats, the level of glucose retained by the preparations was increased (P<0.05) by the presence of insulin, and insulin plus gliclazide in the perfusate. In the presence of insulin and/or gliclazide, the portal lactate levels were not modified, but the alanine levels were reduced (P<0.05) to normal values. In preparations from non-diabetic rats, the level of glucose retained was increased (P<0.05) by gliclazide and insulin plus gliclazide, without modification of the portal lactate and alanine levels. In conclusion, the results show that both insulin and gliclazide increased glucose utilization by perfused intestine-pancreas preparations isolated from diabetic rats. The effect was enhanced when both substances were present simultaneously in the perfusion medium.Presented in part at the 26th annual meeting of the European Association for the Study of Diabetes, Copenhagen, 10–13 September 1990, and at the 4th meeting of the Mediterranean Group for the Study of Diabetes, Madrid, 4–7 March 1993