{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T15:00:00Z","timestamp":1775833200805,"version":"3.50.1"},"reference-count":0,"publisher":"Rockefeller University Press","issue":"1","content-domain":{"domain":["rupress.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1989,1,1]]},"abstract":"<jats:p>The effects of TsIV-5, a toxin isolated from the Brazilian scorpion Tityus serrulatus, on whole-cell and single-channel Na currents were determined in N18 neuroblastoma cells. In whole-cell records at a test potential of -10 mV, external application of 500 nM TsIV-5 slowed inactivation 20-fold and increased peak current by about one-third without changing time-to-peak. Both the steady-state activation and inactivation curves were shifted to more negative potentials. Other alpha scorpion toxins produce similar effects but the single-channel mechanism is not known. TsIV-5 caused a voltage-dependent prolongation of mean single-channel open time such that at a test potential of -60 mV no change was observed, whereas at -20 mV mean open time increased about threefold and prolonged bursting was observed. Macroscopic current reconstructed from summed single-channel records showed a characteristic toxin-induced potentiation of peak current and a 20-fold slowing of the decay phase. TsIV-5 does not discriminate between tissue-specific Na channel subtypes. Prolonged open times and bursting were also observed in toxin-treated Na channels from rat ventricular myocytes, rat cortical neurons, and mouse skeletal muscle. The toxin effects are shown to be consistent with a kinetic model in which TsIV-5 selectively interferes with the ability of the channel to reach the inactivated state.<\/jats:p>","DOI":"10.1085\/jgp.93.1.67","type":"journal-article","created":{"date-parts":[[2004,5,13]],"date-time":"2004-05-13T23:48:59Z","timestamp":1084492139000},"page":"67-83","update-policy":"https:\/\/doi.org\/10.1085\/jgp.crossmarkpolicy","source":"Crossref","is-referenced-by-count":99,"title":["Modification of Na channel gating by an alpha scorpion toxin from Tityus serrulatus."],"prefix":"10.1085","volume":"93","author":[{"given":"G E","family":"Kirsch","sequence":"first","affiliation":[{"name":"Department of Physiology and Molecular Biophysics, Baylor College of Medicine, Houston, Texas 77030."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A","family":"Skatteb\u00f8l","sequence":"additional","affiliation":[{"name":"Department of Physiology and Molecular Biophysics, Baylor College of Medicine, Houston, Texas 77030."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"L D","family":"Possani","sequence":"additional","affiliation":[{"name":"Department of Physiology and Molecular Biophysics, Baylor College of Medicine, Houston, Texas 77030."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A M","family":"Brown","sequence":"additional","affiliation":[{"name":"Department of Physiology and Molecular Biophysics, Baylor College of Medicine, Houston, Texas 77030."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"291","published-online":{"date-parts":[[1989,1,1]]},"container-title":["The Journal of general physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/rupress.org\/jgp\/article-pdf\/93\/1\/67\/1813824\/67.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/rupress.org\/jgp\/article-pdf\/93\/1\/67\/1813824\/67.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,7,27]],"date-time":"2023-07-27T12:29:31Z","timestamp":1690460971000},"score":1,"resource":{"primary":{"URL":"https:\/\/rupress.org\/jgp\/article\/93\/1\/67\/27708\/Modification-of-Na-channel-gating-by-an-alpha"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1989,1,1]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1989,1,1]]}},"URL":"https:\/\/doi.org\/10.1085\/jgp.93.1.67","relation":{},"ISSN":["0022-1295","1540-7748"],"issn-type":[{"value":"0022-1295","type":"print"},{"value":"1540-7748","type":"electronic"}],"subject":[],"published":{"date-parts":[[1989,1,1]]}}}