Extracellular K+ and Ca2+ activities measured during the action of negative pressure under a suction electrode placed on the surface of frog heart ventricle.
The application of negative pressure of -40 kPa (-300 mm Hg) for 10 min under a suction electrode placed on the surface of the spontaneously beating frog ventricle changed the extracellular potassium activity (aoK+) in three phases: a phase of rapidly rising aoK+, a slowly decaying phase and a phase of slowly rising aoK+. The changes reversed when suction was discontinued during the rapidly rising and decaying phase, but were not reversed during the slowly rising phase. Calcium extra-cellular activity (aoCa2+) decreased between -5 and -13 kPa, but increased during the higher pressures. The results indicated that injury of the ventricular tissue caused by a suction electrode elevated aoK+ and altered aoCa2+.
Slavícek
J
J
Vyskocil
F
F
D000200:Action Potentials; D000818:Animals; D002118:Calcium / Q000502:physiology*; D003655:Decerebrate State; D004566:Electrodes; D005110:Extracellular Space / Q000502:physiology*; D006321:Heart / Q000502:physiology*; D006352:Heart Ventricles; D008564:Membrane Potentials; D011188:Potassium / Q000502:physiology*; D011896:Rana temporaria; D011930:Reaction Time; D013396:Suction
D011188:Potassium; D002118:Calcium