@phdthesis{oai:toyama.repo.nii.ac.jp:00005149,
 author = {畠山, 登},
 month = {Mar},
 note = {Sevoflurane is a potent anesthetic that is widely used due to its efficacy in preventing arrhythmias associated with epinephrine.
The mechanism of negative inotropic effect of sevoflurane was examined in the present study on canine single ventricular myocytes.
The effects of sevoflurane on contractile response, membrane potential, membrane ionic currents and intracellular cyclic AMP were studied.
Contractions were measured by a video-edge detector and membrane ionic currents were recorded using whole-cell voltage clamp technique.
Sevoflurane, in concentrations ranging from 1.0% to 4.0%, decreased contraction of single ventricular cells.
These inhibitory effects on the contractile response were dose-dependant and reversible.
In normal Tyrode solution, sevoflurane decreased the plateau of action potentials and shortened the durations.
In high-K^+ (26mM) Tyrode solution, the duration of slow action potential was shortened.
Voltage-clamp experiment with single canine ventricular cells revealed that sevoflurane reduced the peak Ca^<2+> currents (I_<Ca>).
These inhibitory effects of sevoflurane on I_<Ca> did not show use-dependent block.
On the other hand, sevoflurane depressed Na^+ currents (I_<Na>) only in high concentration (4.0%) and had no effect on the inward rectifier K^+ currents (I_<Kl>).
The inhibition of I_<Ca> was not associated with changes in intracellular concentration of cyclic AMP except at a high dose (4.0%).
These results suggest that the negative inotropic effect of sevoflurane is mediated via inhibition of I_<Ca> in canine ventricular cells., Article, 富山医科薬科大学・博士(医学)・甲第172号・畠山登・1993/3/10},
 school = {富山医科薬科大学},
 title = {Effects of sevoflurane on contractile response and electrophysiological properties in single cardiac myocytes of dog},
 year = {1993}
}