CARDIAC MEMBRANE POTENTIALS RECORDED FROM THE INJURED VENTRICULAR CELLS OF DOGS
1959 Volume 9 Issue 3 Pages 375-386
Details
1959 Volume 9 Issue 3 Pages 375-386
The cellular membrane potential of the injured cardiac muscle fiber of the dog was recorded, and its various electrical properties were investigated.
(1) Injury was caused by either of a mechanical compression with a glass tube, burn, and a ligature with a thread. The injured region was unable to impale, but the cells around there could be examined, and showed diminished RP, rise velocity decrease or disappearance of OS of AP. The greater the distance from injury, the less was the degree of impairment.
(2) A short period of hyperpolarization altered neither OS nor rise velocity.
(3) Membrane resistance of the injured cells decreased remarkably.
(4) By injury the threshold (rheobase) was elevated to a higher level as shown in the strengh-duration curves. Absolute refractory period was prolonged until a later phase of more than 80% repolarisation.
(5) There findings were discussed and the author would interprete as follows: the injured membrane loses its ion-selective ability and becomes leaky to ions.
