Calcium and pancreatic beta-cell function: glucose stimulation uptake of lanthanum-displaceable 45-Ca from low or...

The uptake of 45Ca was studied in beta-cell-rich pancreatic islets microdissected from ob/ob-mice. Glucose stimulated 45Ca incorporation in a lanthanum-displaceable pool remaining after correction for the extracellular space occupied by sucrose. It is suggested that the glucose effect on the lanthanum-displaceable calcium is the cause rather than the result of the secretion of insulin since it could be demonstrated also in the presence of only trace amounts of extracellular calcium.