Faculty Collaboration Database

Effects of halothane on transmembrane potentials, Ca2+ transients, and papillary muscle tension in the cat. Am J Physiol 1986 Aug;251(2 Pt 2):H374-81

Date

08/01/1986

Pubmed ID

3740291

DOI

10.1152/ajpheart.1986.251.2.H374

Scopus ID

2-s2.0-0022475722 (requires institutional sign-in at Scopus site)   37 Citations

Abstract

The effects of halothane on cat papillary muscle were studied in vitro at different pacing rates (60, 75, 100, and 150 beats/min). Simultaneous measurements of transmembrane potentials, intracellular Ca2+ transients, and isometric tension were made before and after introduction of 1 and 2 minimal alveolar concentration halothane. Anesthetic concentrations in the superfusion bath were measured using a gas chromatography procedure. The Ca2+-sensitive photoprotein, aequorin, was microinjected into papillary muscle cells. Aequorin light emission is a function of free intracellular [Ca2+] [( Ca2+]i). The most prominent effects of halothane were a dose-dependent decrease in the contractile force and a decrease in [Ca2+]i, at all pacing rates. The negative inotropic effect of halothane was associated with only small changes in the papillary muscle action potential duration. Increasing the extracellular [Ca2+] produced an increase in [Ca2+]i and counteracted the negative inotropic effects of halothane. Addition of the Ca2+ channel blocker, verapamil, and halothane, produced an additive decrease in [Ca2+]i compared with the control.

Author List

Bosnjak ZJ, Kampine JP

Author

Zeljko Bosnjak PhD, MS Emeritus Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Action Potentials
Aequorin
Animals
Calcium
Cats
Halothane
Heart Rate
Membrane Potentials
Myocardial Contraction
Osmolar Concentration
Papillary Muscles
Regression Analysis
Verapamil