title: Effects of sevoflurane on the contractility of ferret ventricular myocardium.
abstract: 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 degrees C) (n = 9). In a second group of muscles (n = 8), effects of sevoflurane were compared with those of low [Ca(2+)](o) (0.45-2.25 mM in steps of 0.45 mM). Sevoflurane caused a reversible concentration-dependent decrease in contractility (ED(50) of developed force 4.6+/-0.9% vol/vol). When compared with twitches of equal amplitude in low extracellular Ca(2+) 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 Ca(2+) availability. The abbreviated isometric relaxation likely reflects a decrease in Ca(2+) sensitivity and the faster isotonic relaxation may reflect a mild stimulation of Ca(2+) uptake by the sarcoplasmic reticulum.
authors.affiliation: Department of Anesthesiology, Mayo Foundation, Rochester, Minnesota 55905, USA.
authors.forename: A E
authors.initials: AE
authors.lastname: Bartunek
authors.forename: P R
authors.initials: PR
authors.lastname: Housmans
mesh_terms: D018685:Anesthetics, Inhalation / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000493:pharmacokinetics; D005289:Ferrets; D006321:Heart / Q000187:drug effects / Q000502:physiology*; D006352:Heart Ventricles / Q000187:drug effects; D007537:Isometric Contraction / Q000187:drug effects; D008297:Male; D008738:Methyl Ethers / Q000494:pharmacology*; D018485:Muscle Fibers, Skeletal / Q000187:drug effects / Q000378:metabolism; D009200:Myocardial Contraction / Q000187:drug effects*; D009206:Myocardium / Q000166:cytology / Q000378:metabolism; D009210:Myofibrils / Q000187:drug effects / Q000378:metabolism; D012519:Sarcoplasmic Reticulum / Q000187:drug effects / Q000378:metabolism; D000077149:Sevoflurane; D016276:Ventricular Function
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane; D002118:Calcium