Membrane surface interactions involved in insulin secretion.

Laser light-scattering techniques have been used to study the effects of polyanions on the time-dependent interaction of (i) polystyrene particles and (ii) insulin-containing granules isolated from pancreatic islets. New evidence of a major effect of polyanions on secretory granule aggregation is presented. The possible importance of intracellular polyanions in restricting the aggregation and hence fusion of secretory granules, especially in the presence of Ca2+, is discussed.