Detailed Information

pH변화가 심실근 경축현상에 미치는 영향 : Effect of Extracellular pH on Contracture in Frog Ventricle

Cited 0 time in Web of Science Cited 0 time in Scopus

김전; 박준; 박영배

Issue Date
서울대학교 의과대학
Seoul J Med, Vol.24 No.2, pp. 175-184
Potassium contractures were induced in isolated
frog(Rana tcmporaria) ventricular strips with trisbuffered
Ringer solutions containing 20~100mM K
ions and concomitantly less Na ions at room temperaturet
lS to 20nC). External pH was raised up to
8.4 or lowered down to 6.4 and its effect upon
K-contracture was investigated to elicit the mechanism
of action of H ions on excitation-contraction
coupling in frog ventricular myocardium.
Followings are the results obtained:
]. At normal pH, biphasic contracture was evoked
at external K concentration of 40mM. On rasing
K concentration to lOOmM, contracture tension
increased gradually and the interval between the
end of contracture and resuming of twitch was also
prolonged. When K-20mM solution was replaced by
normal Ringer solution, twitch tension developed
rapidly and much higher tension than control twitch
was elicited transiently. After the first application
of K-100mM fully recovered tensions were always
smaller than those of control twitch tensions.
2. On raising external pH from normal to 8.4,
there were no significant changes in K-induced contractures
comparing to those evoked under normal
3. On lowering external pH down to 7.4, phasic
portion of K-contractures were augmented within
the range of 20 to 40mM K and tonic portions in
creased gradually with time elapsed at 100mM K
ion concentrations.
From the above results it was concluded that H
ion acted upon contracture induced by high K with low
Na ion" Via the inhibition of Na-K pump during
the early phase and changes in intracellular pII
during the later phase.
Files in This Item:
Appears in Collections:


Item View & Download Count

  • mendeley

Items in S-Space are protected by copyright, with all rights reserved, unless otherwise indicated.