{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T02:46:02Z","timestamp":1771641962100,"version":"3.50.1"},"reference-count":0,"publisher":"Rockefeller University Press","issue":"5","content-domain":{"domain":["rupress.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1965,5,1]]},"abstract":"<jats:p>Electrical and mechanical studies have been made of the deep abdominal extensor muscles, medial (DEAM) and lateral (DEAL), of crayfish and lobster. The medial muscle responds to direct (intracellular) and indirect stimulation with a transient membrane depolarization which exhibits the properties of a propagated non-decremental action potential but does not overshoot the zero level. The amplitude is about 30 mv in crayfish and 50 mv in lobster. It is followed by a fast all-or-none twitch whose duration at 20\u00b0C is 30 to 50 msec. and whose developed tension is 500 gm\/cm2 or about half the tetanic value. Membrane potential is K+-dependent and immersion in high K+ induces a brief transient tension rise as in other twitch-type muscles. The action potential and twitch are normal even if all external Na+ is replaced with sucrose but vary with external Ca++, the action potential increasing 8 to 10 mv for a twofold increase in Ca++. The lateral muscle (DEAL) is much slower and responds to intracellular stimulation only with an electrotonic or a local response. Mechanical responses and relaxation speeds are slow with minimal duration of contraction of 0.5 to 2 seconds. Immersion in high K solutions induces large maintained tensions. Sarcomere length in the fast DEAM is uniform and about 2 \u00b5 at rest, but in the DEAL speed is less and sarcomere length is greater averaging about 4.5 \u00b5 but with a mixed population of fibers.<\/jats:p>","DOI":"10.1085\/jgp.48.5.919","type":"journal-article","created":{"date-parts":[[2004,5,13]],"date-time":"2004-05-13T22:11:52Z","timestamp":1084486312000},"page":"919-931","update-policy":"https:\/\/doi.org\/10.1085\/jgp.crossmarkpolicy","source":"Crossref","is-referenced-by-count":49,"title":["Electrical and Mechanical Responses in Deep Abdominal Extensor Muscles of Crayfish and Lobster"],"prefix":"10.1085","volume":"48","author":[{"given":"Bernard C.","family":"Abbott","sequence":"first","affiliation":[{"name":"From the Department of Physiology and Biophysics, University of Illinois, Urbana"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"I.","family":"Parnas","sequence":"additional","affiliation":[{"name":"From the Department of Physiology and Biophysics, University of Illinois, Urbana"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"291","published-online":{"date-parts":[[1965,5,1]]},"container-title":["The Journal of General Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/rupress.org\/jgp\/article-pdf\/48\/5\/919\/1736351\/919.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/rupress.org\/jgp\/article-pdf\/48\/5\/919\/1736351\/919.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,7,25]],"date-time":"2023-07-25T21:45:03Z","timestamp":1690321503000},"score":1,"resource":{"primary":{"URL":"https:\/\/rupress.org\/jgp\/article\/48\/5\/919\/47530\/Electrical-and-Mechanical-Responses-in-Deep"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1965,5,1]]},"references-count":0,"journal-issue":{"issue":"5","published-print":{"date-parts":[[1965,5,1]]}},"URL":"https:\/\/doi.org\/10.1085\/jgp.48.5.919","relation":{},"ISSN":["1540-7748","0022-1295"],"issn-type":[{"value":"1540-7748","type":"electronic"},{"value":"0022-1295","type":"print"}],"subject":[],"published":{"date-parts":[[1965,5,1]]}}}