Effects of sevoflurane on the contractility of ferret ventricular myocardium

Autor: Philippe R. Housmans, Anna E. Bartunek
Rok vydání: 2000
Předmět:
Zdroj: Journal of Applied Physiology. 89:1778-1786
ISSN: 1522-1601
8750-7587
DOI: 10.1152/jappl.2000.89.5.1778
Popis: Isotonic and isometric variables of contractility and relaxation of isolated ferret right ventricular papillary muscles were measured before and during exposure to incremental concentrations of sevoflurane (0–4.9% vol/vol) (30°C) ( n = 9). In a second group of muscles ( n = 8), effects of sevoflurane were compared with those of low [Ca2+]o(0.45–2.25 mM in steps of 0.45 mM). Sevoflurane caused a reversible concentration-dependent decrease in contractility (ED50of developed force 4.6 ± 0.9% vol/vol). When compared with twitches of equal amplitude in low extracellular Ca2+concentration, sevoflurane accelerated both isometric and isotonic relaxation. The myocardial depressant effect of sevoflurane is less than that of isoflurane and results mainly from a decrease of intracellular Ca2+availability. The abbreviated isometric relaxation likely reflects a decrease in Ca2+sensitivity and the faster isotonic relaxation may reflect a mild stimulation of Ca2+uptake by the sarcoplasmic reticulum.
Databáze: OpenAIRE