{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,6,17]],"date-time":"2024-06-17T20:40:12Z","timestamp":1718656812163},"reference-count":0,"publisher":"Canadian Science Publishing","issue":"6","license":[{"start":{"date-parts":[[1991,6,1]],"date-time":"1991-06-01T00:00:00Z","timestamp":675734400000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/www.nrcresearchpress.com\/page\/about\/CorporateTextAndDataMining"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Can. J. Physiol. Pharmacol."],"published-print":{"date-parts":[[1991,6,1]]},"abstract":"<jats:p> The effects of caffeine, ryanodine, and rapid cooling were tested on the depolarization-induced contraction and the apamin-insensitive slow outward current (I<jats:sub>so<\/jats:sub>) of voltage-clamped (double mannitol gap) single frog muscle fibers. Subthreshold caffeine concentrations (0.5\u20132\u2002mM) induced a monotonic increase in contractile and I<jats:sub>so<\/jats:sub> amplitude. Whatever the concentration, the increase in contraction was roughly twice the one in current. Similar results were obtained upon rapid cooling (20\u20134 \u00b0C) in the presence of 0.5\u2002mM caffeine. In the absence of external Na<jats:sup>+<\/jats:sup> (choline-substituted) 10<jats:sup>\u22125<\/jats:sup>\u2002M ryanodine induced a delayed increase (\u224830\u2002min) in contraction and in current, shortly before the development of a drastic and irreversible contracture. Here again, the increase in contraction was twice that in current. In the presence of 5\u2002mM tetraethylammonium (TEA) and (or) 25\u2002nM charybdotoxin, 2\u2002mM caffeine still induced a strong facilitating effect on contraction but the parallel increase in current was strongly reduced. The linear relationship between the increase in current and contractile amplitude has a slope \u22480.5 (whatever the drug used to increase contractility); it is \u22480.1 in the presence of TEA and (or) charybdotoxin. In conclusion, provided the changes in contractile amplitude are caused by parallel changes in depolarization-induced sarcoplasmic reticulum Ca<jats:sup>2+<\/jats:sup> release, about 50% of the apamin-insensitive I<jats:sub>so<\/jats:sub> is controlled by internal Ca<jats:sup>2+<\/jats:sup> release. The main part of this current corresponds to the TEA- and charybdotoxin-sensitive component of I<jats:sub>so<\/jats:sub>.Key words: skeletal muscle, voltage clamp, Ca<jats:sup>2+<\/jats:sup>-dependent K<jats:sup>+<\/jats:sup> current, sarcoplasmic reticulum calcium release, caffeine, ryanodine, charybdotoxin. <\/jats:p>","DOI":"10.1139\/y91-130","type":"journal-article","created":{"date-parts":[[2011,4,24]],"date-time":"2011-04-24T08:58:18Z","timestamp":1303635498000},"page":"859-864","source":"Crossref","is-referenced-by-count":0,"title":["The correlation between the increase in slow outward current and in contraction induced by caffeine, ryanodine, and rapid cooling in voltage-clamped frog muscle fibers"],"prefix":"10.1139","volume":"69","author":[{"given":"Mohammad","family":"Nasri-Sebdani","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Flavien","family":"Traor\u00e9","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aklesso","family":"Mouzou","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christian","family":"Cognard","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel","family":"Potreau","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guy","family":"Raymond","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"155","container-title":["Canadian Journal of Physiology and Pharmacology"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/www.nrcresearchpress.com\/doi\/pdf\/10.1139\/y91-130","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2020,1,5]],"date-time":"2020-01-05T15:24:02Z","timestamp":1578237842000},"score":1,"resource":{"primary":{"URL":"http:\/\/www.nrcresearchpress.com\/doi\/10.1139\/y91-130"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1991,6,1]]},"references-count":0,"journal-issue":{"issue":"6","published-print":{"date-parts":[[1991,6,1]]}},"alternative-id":["10.1139\/y91-130"],"URL":"https:\/\/doi.org\/10.1139\/y91-130","relation":{},"ISSN":["0008-4212","1205-7541"],"issn-type":[{"value":"0008-4212","type":"print"},{"value":"1205-7541","type":"electronic"}],"subject":[],"published":{"date-parts":[[1991,6,1]]}}}