Nicorandil, a K⁺ channel opener is frequently used in ischaemic heart disease (IHD). Diabetes mellitus is often associated with IHD. There is a possibility of alteration of blood glucose level (BGL) by nicorandil when used with sulfonylureas by influencing insulin release as it’s a K⁺ channel opener. The study has been done to know the changes of BGL after administration of low-dose nicorandil with sulfonylureas in Diabetic as well as normal rabbits. The study has been done on normal and alloxan induced diabetic rabbits by keeping them 12 hrs fasting & water ad lib. Glibenclamide was given in a dose of 50µg/kg body weight &Nicorandil was administered in a dose of 10,20,40,80 and160µg/kg body weight concurrently. The drugs were given by oral route. Normal saline treated rabbits were used as control. Blood samples were collected from marginal ear vein & BGL was estimated in the process described by Hultmann. The statistical significance was calculated by employing student “t” test. Glibenclamide per se in a dose of 50 µg/kg produced significant hypoglycemia, Nicorandil in in doses of 20µg/kg abolishes the hypoglycemic effect of glibenclamide, & in dose of 40µg/kg produced significant hyperglycemia. Nicorandil, a K⁺ channel opener can increase blood glucose level by its action probably on ATP sensitive K⁺ channel of β cells of pancreas only at a certain dose range (20 to40 µg/kg body weight doses) for 2 to 3 hours., but no change in BGL in 80 and 160 µg/kg body weight doses which are also relatively low doses than conventional dose. The sensitivity of low dose nicorandil is more than sulfonylureas on β cells of pancreas & the response is dose dependent. In alloxan induced diabetic rabbit, the change in BGL is not so marked probably due to lack of β cells of pancreas.

Keywords: Blood Glucose, Nicorandil, Sulphonylureas.

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Dr Anupam Nath Gupta

Associate Professor, Department of Pharmacology, North Bengal Medical College, Darjeeling, West Bengal