Constriction ability of coronary artery in volume overload cardiac hypertrophy.
The constrictor response of the rabbit conduit coronary artery from hypertrophied heart (volume-overload stabilized hypertrophy) was studied to vasoactive substances. The heart/body weight ratio was 2.67 +/- 0.95 in the experimental group and 1.90 +/- 0.09 in the controls. The responses to acetylcholine, serotonin and potassium chloride was dose-dependent in the controls: the maximum amounted to 9.07 +/- 2.03 mN, 6.00 +/- 1.79 and 10.94 +/- 1.64 mN, respectively. Remarkably lower responses were detected in coronary arteries from hypertrophied hearts in the whole range of concentrations applied; the maximum was only 22.34 +/- 8.32% of the control response to acetylcholine, 17.83 +/- 11.37% to serotonin, and 21.74 +/- 5.50% to potassium chloride. A disbalance between stabilized cardiac hypertrophy and the remarkably low constrictor ability of the conduit coronary artery has been described.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D006332:Cardiomegaly / Q000209:etiology / Q000503:physiopathology*; D003331:Coronary Vessels / Q000187:drug effects / Q000503:physiopathology*; D005260:Female; D006439:Hemodynamics; D066298:In Vitro Techniques; D008297:Male; D011189:Potassium Chloride / Q000494:pharmacology; D011817:Rabbits; D012701:Serotonin / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects
D012701:Serotonin; D011189:Potassium Chloride; D000109:Acetylcholine