This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Brooks, C. McC. Articles by BIANCHI, C. P. Search for Related Content PubMed Articles by Brooks, C. McC. Articles by BIANCHI, C. P.

(Circulation. 1961;24:518.)
© 1961 American Heart Association, Inc.

---

Calcium Movements in Muscle

Chandler McC. Brooks Ph.D. C. PAUL BIANCHI PH.D.¹

¹ From the Institute for Muscle Disease, New York, New York.

The movements of calcium in muscle have been followed during contraction and contracture to test the hypothesis that the release of calcium from the surface of the muscle membrane during stimulation initiates the contractile mechanism. Nitrate ion increases the calcium influx during a single twitch and during potassium contracture, and also increases the tension developed. The increased entry of calcium during a potassium contracture is transient and not sustained as is the contracture. Caffeine, which brings about a contracture without depolarization of the membrane and despite the absence of calcium from the medium, causes calcium to be released from the muscle.

This article has been cited by other articles:

				H. Rasmussen Cell Communication, Calcium Ion, and Cyclic Adenosine Monophosphate Science, October 23, 1970; 170(3956): 404 - 412. [Abstract] [PDF]