title: Involvement of cellular cyclic AMP in theophylline-induced sugar accumulation in chicken intestinal epithelial cells.
abstract: We have studied the possible involvement of cellular cyclic AMP in theophylline-induced sugar gradient enhancement in isolated chicken enterocytes. Theophylline increases 3-O-methylglucose accumulation 3-fold after 30 min incubation. Exogenous cyclic AMP enhances sugar accumulation by 48%. Adenylyl cyclase inhibitor RMI 12 330A reduces theophylline-induced sugar gradients by 22% and theophylline-induced cyclic AMP levels by 24.5%. At the concentration used, RMI 12 330A has no effect on 3-O-methylglucose accumulation or basal cellular cyclic AMP. Since theophylline has a rapid inhibitory effect on Na+-independent sugar permeability, we conclude that the effects of the drug on sugar gradients are the result of its acting by both direct - surface membrane - and indirect - cyclic AMP mediated - mechanisms. The effect of theophylline and exogenous cyclic AMP on sugar accumulation is independent of external chloride.
mesh_terms: D019325:3-O-Methylglucose; D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D002645:Chickens; D000242:Cyclic AMP / Q000378:metabolism*; D003837:Deoxy Sugars / Q000378:metabolism*; D003847:Deoxyglucose / Q000378:metabolism*; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism*; D007700:Kinetics; D008757:Methylglucosides / Q000378:metabolism*; D008759:Methylglycosides / Q000378:metabolism*; D012964:Sodium / Q000494:pharmacology; D013806:Theophylline / Q000494:pharmacology*
chemical_list: D003837:Deoxy Sugars; D008757:Methylglucosides; D008759:Methylglycosides; D019325:3-O-Methylglucose; C027020:methylglucoside; D003847:Deoxyglucose; D012964:Sodium; D013806:Theophylline; D000242:Cyclic AMP