Premium
Decrease in ionic permeability of the cell membrane in guinea‐pig atrial tissue by treatment with antifibrillatory agents and hexobarbitone, determined by means of 86 Rb
Author(s) -
ZWIETEN P. A. van
Publication year - 1969
Publication title -
british journal of pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.432
H-Index - 211
eISSN - 1476-5381
pISSN - 0007-1188
DOI - 10.1111/j.1476-5381.1969.tb07970.x
Subject(s) - quinidine , chemistry , guinea pig , propranolol , biophysics , permeability (electromagnetism) , inotrope , membrane permeability , membrane , membrane potential , pharmacology , medicine , endocrinology , biochemistry , biology
1 The influence of antifibrillatory agents on the release of previously accumulated 86Rb + ions was studied in guinea‐pig isolated left auricles, incubated in a K + ‐free Tyrode solution that contained an equivalent concentration (2.7 m m ) of Rb + . The auricles were stimulated electrically at a frequency of 100/min and showed entirely “normal” mechanical behaviour in the incubation medium. 2 Quinidine, tetracaine, hexobarbitone‐Na and propranolol caused a dose‐dependent negative inotropic effect. The frequency of beating (100/min) was usually not affected by these drugs. 3 The reduction in contractile force was accompanied by a dose‐dependent inhibition of 86 Rb release. The concentration‐response curves for both the mechanical effect and the influence on 86 Rb release almost coincided for quinidine, although these curves diverged for the other drugs studied. 4 It is suggested that all the four different antifibrillatory drugs cause a general reduction of the membrane permeability to inorganic ions. The mechanism of this membrane stabilization remains unknown.