Zinc-induced inhibition of insulin secretion from isolated rat islets of Langerhans

T Ghafghazi, ML McDaniel, PE Lacy - Diabetes, 1981 - Am Diabetes Assoc
T Ghafghazi, ML McDaniel, PE Lacy
Diabetes, 1981Am Diabetes Assoc
The present experiments indicate that ZnCl2 (0.015–0.50 mM) inhibits in a dose-dependent
manner insulin secretion from isolated rat islets stimulated by D-glucose, L-leucine, and
potassium. This inhibitory effect is partially reversed by washing and antagonized by high
calcium concentrations in the medium. Zinc levels that inhibit insulin release do not affect
45calcium uptake, and zinc will not replace calcium in triggering insulin release. The
conversion of 14C-D-glucose to 14CO2 by islets is not modified by zinc (0.12 mM or 0.50 …
The present experiments indicate that ZnCl2 (0.015–0.50 mM) inhibits in a dose-dependent manner insulin secretion from isolated rat islets stimulated by D-glucose, L-leucine, and potassium. This inhibitory effect is partially reversed by washing and antagonized by high calcium concentrations in the medium. Zinc levels that inhibit insulin release do not affect 45calcium uptake, and zinc will not replace calcium in triggering insulin release. The conversion of 14C-D-glucose to 14CO2 by islets is not modified by zinc (0.12 mM or 0.50 mM) following either 2- or 0.5-h incubation periods, respectively. It is concluded that the inhibitory effect of zinc on insulin secretion may, in part, be mediated through interference with an intracellular function of calcium by the β-cell.
Am Diabetes Assoc