Effect of propranolol and nitroglycerin on hemoglobin--oxygen affinity.
The effect of propranolol on the oxyhemoglobin dissociation curve (P-50) of coronary venous blood was studied in isolated canine hearts. I.v. administration of propranolol (0.5, 5.0 mg/kg) produced no significant change in P-50 over 4 hr. Following propranolol, an intracoronary infusion of nitroglycerin (10 mug/min) increased P-50. Addition of propranolol (5 X 10(-5) M to 1 X 10(-4)M) to central venous blood in vitro produced a significant increase in P-50. These data indicate that propranolol increases P-50 in vitro but does not increase P-50 in vivo, whereas nitroglycerin increases P-50 In vivo but not in vitro.
D000818:Animals; D001784:Blood Gas Analysis; D003331:Coronary Vessels; D004285:Dogs; D006439:Hemodynamics / Q000187:drug effects; D006454:Hemoglobins / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism; D005996:Nitroglycerin / Q000494:pharmacology*; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption; D010108:Oxyhemoglobins; D011433:Propranolol / Q000494:pharmacology*
D006454:Hemoglobins; D010108:Oxyhemoglobins; D011433:Propranolol; D005996:Nitroglycerin; D010100:Oxygen