Functional and biochemical interaction of dibutyryl cyclic AMP with the phosphoinositide system in isolated rat parietal cells.
The interaction of the muscarinic agonist carbachol and of dibutyryl cAMP on acid secretion and phosphoinositide second messenger metabolism were studied in rat gastric parietal cells. Compared to the added effects of each agonist alone aminopyrine uptake, a measure of acid secretion, was enhanced 2-4-fold by the combination of both compounds. In addition the ED50 for carbachol was left shifted in the presence of dibutyryl-cAMP. The cholinergic stimulation of inositol phosphate production was slightly inhibited by dibutyryl-cAMP while levels of diacylglycerol were not affected. Thus the interaction of the cAMP and the phosphoinositide systems involve potentiation and positive sensitivity modulation of the cholinergic response by cAMP which is mediated by events distal to the generation of phosphoinositide second messengers.
Pfeiffer
A
A
Sauter
G
G
Rochlitz
H
H
D000632:Aminopyrine / Q000378:metabolism; D000818:Animals; D003994:Bucladesine / Q000494:pharmacology*; D002217:Carbachol / Q000494:pharmacology; D004075:Diglycerides / Q000096:biosynthesis; D015544:Inositol 1,4,5-Trisphosphate; D007295:Inositol Phosphates / Q000096:biosynthesis; D007700:Kinetics; D010295:Parietal Cells, Gastric / Q000187:drug effects / Q000378:metabolism*; D010716:Phosphatidylinositols / Q000096:biosynthesis*; D051381:Rats
D004075:Diglycerides; D007295:Inositol Phosphates; D010716:Phosphatidylinositols; D000632:Aminopyrine; D003994:Bucladesine; D015544:Inositol 1,4,5-Trisphosphate; D002217:Carbachol