The effects of an electron dense thiol reagent, Hg phenylazo ferritin, on β cell ultrastructure was studied in cell suspensions from mouse pancreatic islets. This type of thiol reagent induced severe damage in the β cells. The ferritin particles were traced with the electron microscope and found to be bound to the plasma membrane as well as to various cytoplasmic structures. The β cell cytotoxic action of Hg phenylaxo ferritin was inhibited by L cysteine. The data conform with the assumption that there are highly reactive SH groups on the β cell surface, whose blocking may induce conformational changes in the plasma membrane and alter its permeability. The thiol reagent had no significant effect on insulin release from intact, microdissected mouse islets, probably owing to its poor penetrating ability.
|Number of pages||6|
|Publication status||Published - 1974 Dec 1|