In isolated rat pancreatic islets, the effect of diamide and N-ethylmaleimide (NEM)
on forskolin- as well as on glucagon-induced elevation of cAMP was studied. Forskolin
and glucagon increased cAMP levels in batch-incubated islets. Diamide and NEM further
augmented forskolin-induced increase of cAMP levels, whereas glucagon-stimulated elevation
of cAMP was not affected. From our data it is likely that under the conditions of
the present study, the thiols related to the Ns-protein and the catalytic unit are insensitive to oxidation and alkylation. The potentiation
of forskolin-induced cAMP production in intact islet cells by diamide and NEM may
be due to inactivation of the thiols related to the Ni-protein.
Pancreatic Islets - Ni-Protein - Forskolin - Thiolreagents
