The effects of carbon monoxide on the heart: an in vitro study.
Experiments were conducted to assess the effects of increasing concentrations of carbon monoxide (CO) on the isolated spontaneously beating rat heart. Hearts removed from male Sprague Dawley rats were perfused via the aorta with Krebs-Henseleit solution. Coronary flow was timed and collected in a calibrated vessel. Heart rate and pulse pressure were measured by a catheter inserted in the left ventricle and attached to a pressure transducer. After 30 min, the hearts were challenged for 10 min with perfusate containing increasing concentrations of CO and decreasing concentrations of 02. Coronary flow increased in response to CO concentrations below 50%. After 8 min, coronary flow increased by 40% in response to 10% CO challenge. Heart rate and pulse pressure were generally depressed by CO. Heart rate was depressed at the end of 8 min by 5, 10, 38, and 64%, respectively, by solutions equilibrated against 10, 25, 50, and 95% CO. Pulse pressure decreased with concentrations of 50% CO and above. These results indicate that coronary flow appears to be the most sensitive indicator of CO toxicity in the isolated heart.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002248:Carbon Monoxide / Q000494:pharmacology*; D003326:Coronary Circulation / Q000187:drug effects; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D010100:Oxygen; D011674:Pulse / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D013997:Time Factors
D002248:Carbon Monoxide; D010100:Oxygen