The preparation of, and studies on, free cell suspensions from mouse pancreatic islets

Abstract

Pancreatic islets, isolated from the pancreas of obese-hyperglycemic mice, were used to prepare free islet cells in suspension. Batches of 100 islets were disrupted by mechanical shaking for 10 sec in a Ca2+-free HEPES-buffered Krebs-Ring'er medium containing 1 mM EGTA. From 200-500 islets, about 2.2×106 cells could be obtained in suspension, corresponding to a yield of roughly 55% as calculated from the content of DNA in cells and islets. The isolated islet cells appeared well-preserved in the light and the electron microscope and seemed to exhibit a high degree of viability as judged by viable cell counts, a radioactive assay for lysis and insulin release. Insulin release from islet cell suspensions, as calculated per cell, per content of DNA or insulin or per packed cell volume, was stimulated by glucose alone or in combination with theophylline. The glucose response was low compared with that of intact isolated islets. © 1974 Springer-Verlag.