Increased adenosine triphosphatase activity in platelets of asthmatic children.
Adenosine triphosphatase (ATPase) activities were compared in platelets of asthmatic and nonasthmatic children. Significantly elevated Mg2+- and Ca2+-dependent ATPase activities were found in particulate and soluble fractions of platelets from nonsteroid-treated asthmatic children compared to steroid-treated asthmatic and nonasthmatic children. The most pronounced increase (greater than twofold) occurred in the Ca2+-ATPase of the soluble fraction which contains platelet contractile protein. Intact cell surface of ecto ATPase activity was not significantly increased in platelets of asthmatic children. The findings are consistent with adrenergic imbalance in asthma involving depressed adenylate cyclase activity (beta-adrenergic) and increased ATPase activity (alpha-adrenergic) and may relate to abnormal platelet aggregation patterns.
D000244:Adenosine Diphosphate / Q000096:biosynthesis; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000262:Adenylyl Cyclases / Q000378:metabolism; D000293:Adolescent; D001249:Asthma / Q000097:blood* / Q000188:drug therapy / Q000201:enzymology; D001792:Blood Platelets / Q000201:enzymology*; D001798:Blood Proteins / Q000032:analysis; D002118:Calcium / Q000378:metabolism; D002648:Child; D004809:Ephedrine / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000032:analysis; D008274:Magnesium / Q000378:metabolism; D008297:Male; D010634:Phenobarbital / Q000627:therapeutic use; D010974:Platelet Aggregation; D011241:Prednisone / Q000627:therapeutic use; D012882:Skin Tests; D012995:Solubility; D013010:Sonication; D013347:Subcellular Fractions / Q000201:enzymology; D013806:Theophylline / Q000627:therapeutic use
D001798:Blood Proteins; D007073:Immunoglobulin E; D000244:Adenosine Diphosphate; D013806:Theophylline; D000251:Adenosine Triphosphatases; D000262:Adenylyl Cyclases; D004809:Ephedrine; D008274:Magnesium; D002118:Calcium; D011241:Prednisone; D010634:Phenobarbital