Regulation of 86Rb outflow from pancreatic islets. IV. Effect of cyclic AMP, dibutyryl-cyclic AMP and theophylline.
Theophylline (1.4 mM), cyclic AMP (1.0 mM) and dibutyryl-cyclic AMP (0.5 mM) decreased 86Rb fractional outflow rate from pancreatic islets perifused in the absence of glucose. In the presence of glucose (16.7 mM), however, the same drugs provoked a modest increase in 86Rb fractional outflow rate. The increase in 86Rb outflow evoked by theophylline in the presence of glucose was suppressed by quinine, suggesting that it may result from an increase in cytosolic Ca2+ concentration. It is proposed that changes in the cyclic AMP content of islet cells may participate in the regulation of K+ conductance by insulin secretagogues.
D000818:Animals; D003994:Bucladesine / Q000494:pharmacology*; D000242:Cyclic AMP / Q000494:pharmacology*; D005260:Female; D005947:Glucose / Q000494:pharmacology; D066298:In Vitro Techniques; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D011803:Quinine / Q000494:pharmacology; D011868:Radioisotopes; D051381:Rats; D012413:Rubidium / Q000378:metabolism*; D013806:Theophylline / Q000494:pharmacology*
D011868:Radioisotopes; D003994:Bucladesine; D011803:Quinine; D013806:Theophylline; D000242:Cyclic AMP; D005947:Glucose; D012413:Rubidium; D011188:Potassium