title: Inhibition by p-nitrophenylphosphate of acetylcholine release induced by Na+-deprivation.
abstract: The effect of p-nitrophenylphosphate (p-NPP) on the release of acetylcholine evoked by drugs and ionic environments known to inhibit Na+, K+-ATPase was studied in isolated cortical slices of rat brain and longitudinal muscle strip of guinea-pig ileum. p-NPP inhibited the release of acetylcholine induced by sodium deprivation provided that the circumstances were in favour of the function of the K+-activated part of ATPase. However, it failed to antagonize the increase in the acetylcholine release elicited by omission of K+ or by administration of ouabain. Therefore it is concluded that the K+-stimulated phosphatase moiety of the Na+, K+-ATPase might be involved in the release of acetylcholine.
mesh_terms: D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D005260:Female; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects / Q000378:metabolism; D008297:Male; D009596:Nitrophenols / Q000494:pharmacology*; D009943:Organophosphorus Compounds / Q000494:pharmacology*; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D012964:Sodium / Q000502:physiology*; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors
chemical_list: D009596:Nitrophenols; D009943:Organophosphorus Compounds; C008644:nitrophenylphosphate; D010042:Ouabain; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase; D000109:Acetylcholine; D011188:Potassium