EFFECTS OF NICOTINAMIDE ON PREVENTION AND TREATMENT OF STREPTOZOTOCIN-INDUCED DIABETES MELLITUS IN RATS

摘要

Objective. To study the effect of nicotinamide (NAA) on prevention and treatment of STZ-induced diabetes mellitus in rats. Material and Methods. 30 Sprague-Dawley rats were randomly divided inot three groups: 20 rats were given NAA 1 g/ kg /day intramuscularly (10 rats) or orally (10 rats) as experimental groups and the other 10 rats by normal saline orally as control group. Three days later, all 30 rats received streptozotocin (STZ) 55 mg/kg by intraperitioneal injection and took NAA or normal saline continuously as described above for 14 days. During the study, fasting blood glucose (FBG) was measured before and 72 hours after STZ injection and every 2-3 days later on with Glucometer, 24 hours urinary glucose excretion (UGE) was determined once every 4 days with glucose oxidase, body weight was determined every week, the volume of 24-hour water intake and urine excretion were determined twice and once a week respectively. Results. Two weeks after STZ injection, FBG and 24 hours UGE of all rats taking NAA were normal or nearly normal, islet function and morphology revealed no significant differences compared with those of the normal, whereas all rats of control group remained hyperglycemic ( > 16.6 mmol / L) and markedly higher 24 hours UGE as compared with the normal; islets appeared atrophic with decrement of B cell population. Conclusions. The results showed that NAA may effectively prevent the occurrence of STZ-induced diabetes mellitus in rats, suggesting that NAA may be an effective agent for prevention and treatment of insulin-dependent diabetes mellitus (IDDM) in prediabetic and early stage of IDDM.