Hagiya K, Takahashi H, Isaka Y, Inomata S, Tanaka M. Influence of acidosis on cardiotonic effects of colforsin and epinephrine: a dose-response study.
J Cardiothorac Vasc Anesth 2012;
27:925-32. [PMID:
23266286 DOI:
10.1053/j.jvca.2012.09.019]
[Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Indexed: 11/11/2022]
Abstract
OBJECTIVE
Acidosis produces a negative inotropic effect on cardiac muscle against which catecholamines and phosphodiesterase III inhibitors have limited therapeutic effects. This study evaluated the effects of colforsin, which directly activates adenylate cyclase without β-adrenergic receptor activation, in isolated Langendorff rat hearts in a pH- and concentration-dependent manner.
DESIGN
Experimental animal study.
SETTING
A university laboratory.
PARTICIPANTS
Sprague-Dawley rats.
INTERVENTIONS
Hearts were isolated and perfused with 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid/Tyrode solution (pH 7.4) in the Langendorff preparation. The hearts were assigned randomly to the control (pH 7.4), mild acidosis (pH 7.0), or severe acidosis (pH 6.6) group (n = 8 per group) and were perfused continuously with colforsin 10(-7), 10(-6), and 10(-5) mol/L.
MEASUREMENTS AND MAIN RESULTS
Maximum dP/dt was determined, and the concentration-response relation was evaluated at each pH. Colforsin at 10(-6) mol/L increased the maximum dP/dt from 2,592 ± 557 to 5,189 ± 721 mmHg/s (p < 0.001) and from 1,942 ± 325 to 3,399 ± 608 mmHg/s (p < 0.001) in the control and mild acidosis groups, respectively; whereas colforsin, 10(-5) mol/L, significantly increased the maximum dP/dt even in the severe acidosis group. No significant difference was seen in maximum dP/dt among the 3 groups after infusion with colforsin 10(-5) mol/L.
CONCLUSIONS
In contrast to catecholamines and other inodilators, colforsin at a high concentration restores decreased cardiac contractility against severe acidosis to an extent similar to physiologic pH.
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