ATP stimulates inositol phosphates accumulation and calcium mobilization in a primary culture of rat aortic myocytes.
The effects of extracellular ATP on phosphoinositide metabolism and intracellular Ca2+ concentration were studied in a primary culture of rat aortic myocytes. ATP increases the level of inositol phosphates, the putative second messenger for Ca2+ mobilization. No saturation of inositol phosphates accumulation is obtained (up to 10(-2) M ATP). Under the same conditions, ATP rapidly mobilizes intracellular Ca2+ in fura-2 loaded myocytes. The mobilization of intracellular Ca2+ is dose-dependent (maximal at 10(-4) M ATP), and is not affected by addition of EGTA. It is concluded that the receptors mediating the cytosolic increase of Ca2+ are of the P2-purinoceptor subtype. The physiological functions of these receptors are not presently known.
D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D001572:Benzofurans; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D002712:Chlorides / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D016257:Fura-2; D007295:Inositol Phosphates / Q000378:metabolism*; D008094:Lithium / Q000494:pharmacology; D018021:Lithium Chloride; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D013403:Sugar Phosphates / Q000378:metabolism*
D001572:Benzofurans; D002712:Chlorides; D007295:Inositol Phosphates; D013403:Sugar Phosphates; D000804:Angiotensin II; D000255:Adenosine Triphosphate; D008094:Lithium; D018021:Lithium Chloride; D002118:Calcium; D016257:Fura-2