Effect of isometric exercise on catecholamines in the coronary circulation.
Arterial and coronary sinus blood levels of catecholamines, adenosine 3', 5'-cyclic monophosphate (c-AMP) and lactate were measured during isometric exercise in fourteen patients. In no patient did lactate production occur. Mean resting total catecholamine levels both arterial (0.53 +/- 0.07 ng/ml; 2.94 +/- 0.38 nmol/l) and coronary sinus (0.4 +/- 0.08 ng/ml; 2.22 +/- 0.44 nmol/l), did not change significantly on exercise. Coronary sinus c-AMP levels fell on exercise from 11.5 +/- 0.8 nmol/l (resting) to 9.9 +/- 0.8 nmol/l (exercise) (P less than 0.01) with an arterial-coronary sinus difference of 1.2 nmol/l (P less than 0.01) on exercise. Our findings suggest that isometric exercise does not normally result in excessive cardiac symphathetic activity.
D000328:Adult; D000368:Aged; D001794:Blood Pressure; D002395:Catecholamines / Q000097:blood*; D003326:Coronary Circulation; D000242:Cyclic AMP / Q000097:blood; D005260:Female; D006339:Heart Rate; D006801:Humans; D007537:Isometric Contraction; D007773:Lactates / Q000097:blood; D008297:Male; D008875:Middle Aged; D005082:Physical Exertion
D002395:Catecholamines; D007773:Lactates; D000242:Cyclic AMP