Summary
-
(1)
The properties of the contraction produced by break of a constant current are similar to those of the alternating current off-contracture; the make contraction resembles that produced by alternating current.
-
(2)
The muscle responds to break of a constant current when it may be inexcitable to all other forms of stimulation; it may respond when all the sodium chloride of the saline is replaced with chlorides of lithium, ammonium, potassium, calcium, magnesium and strontium or in acid solutions (pH 5).
-
(3)
Magnesium and adrenaline abolish the break contraction.
-
(4)
The response differs with polarity of the direct current; this suggests that the permeability of the membranes is different in the two directions. Stimulation by alternating current is probably due, therefore, to rectification.
-
(5)
The make and the break contractions bear a reciprocal relation to each other.
-
(6)
With polar stimulation, the results are very complicated; contraction or inhibition may occur at the anode or the cathode on make or break of the current.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Heilbrunn, L. V.Outiine of General Physiology, London, 1937.
Singh, I.J. Physiol., 1937,89, 8; 1938a,92, 62; 1938b,94, 1;Proc Ind. Acad. Sci., 1944,20, 195.
- and Singh, I.Proc. Ind. Acad. Sci., 1947. (In the press).
Wiggers, C. J.Physiology in Health and Disease, London, 1944, p. 122.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Singh, I., Singh, S.I. The action of direct current on unstriated muscle. Proc. Indian Acad. Sci. 26, 211–217 (1947). https://doi.org/10.1007/BF03051844
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF03051844