Abstract
In the isolated perfused dog heart, at constant coronary blood flow and heart rate, we studied the effect of altering CO 2 in the gas mixture from 5 to 15% on contractility, coronary resistance, myocardial O 2 consumption and K balance. Contractility, assessed by the developed force, and its derivative through a strain-gauge arch sewn to the left ventricle decreased to 54 ± 7% (p<0.01) and 59 ± 6% (p< 0.01), respectively from control values. Coronary resistance decreased to 79 ± 3% of control (p<0.01). The negative inotropic effect of hypercapnia was accompanied by a decrease in myocardial O 2 consumption to 68 ± 11% (p<0.01) of control value and a net uptake of K by the heart. The possibility of an exchange of H + by K + is suggested as a possible mechanism involved in the negative inotropic effect of hypercapnia.
Translated title of the contribution | Effects of acute hypercapnia upon the myocardium: Contractility, coronary resistance, oxygen consumption and potassium balance |
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Original language | Spanish |
Pages (from-to) | 72-79 |
Number of pages | 8 |
Journal | Acta Physiologica Latino-Americana |
Volume | 27 |
Issue number | 2 |
State | Published - Dec 1 1977 |
ASJC Scopus subject areas
- Physiology
- Pharmacology