Lack of acute zinc effects in glucose metabolism in healthy and insulin-dependent diabetes mellitus patients

Acute or chronic zinc administration may cause hyperglycemia in experimenta l animals. These findings are attributed to permissive actions of glucocort icoids and glucagon upon hepatic gluconeogenesis and glycogenolysis. The ef fect of Zn++ on plasma glucose, C-peptide, glucagon, and cortisol was inves tigated in healthy and insulin-dependent diabetes mellitus (IDDM) patients. Ten normal individuals (5 of each sex, aged 24.10 +/- 1.96) and 10 IDDM (5 of each sex, aged 25.20 +/- 8.10) were tested at 7:00 AM after 12-h fast. Twenty-five mg of Zn++ were administered intravenously during 1 min, and bl ood samples were collected from the contralateral arm at 0, 3, 30, 60, 90 a nd 120 min after Zn++ injection. The plasma levels of glucose, C-peptide, a nd glucagon remained constant throughout the experimental period in both gr oups studied. Plasma cortisol levels decreased significantly, which is cons istent with our previous findings. These results suggest that, in contrast to experimental animals, acute Zn++ administration, despite decreasing cort isol levels, does not change carbohydrate metabolism in human beings.