{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T06:59:18Z","timestamp":1782802758232,"version":"3.54.5"},"reference-count":0,"publisher":"Rockefeller University Press","issue":"3","content-domain":{"domain":["rupress.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1989,3,1]]},"abstract":"<jats:p>We studied the membrane currents of isolated cultured brown fat cells from neonatal rats using whole-cell and single-channel voltage-clamp recording. All brown fat cells that were recorded from had voltage-gated K currents as their predominant membrane current. No inward currents were seen in these experiments. The K currents of brown fat cells resemble the delayed rectifier currents of nerve and muscle cells. The channels were highly selective for K+, showing a 58-mV change in reversal potential for a 10-fold change in the external [K+]. Their selectivity was typical for K channels, with relative permeabilities of K+ greater than Rb+ greater than NH+4 much greater than Cs+, Na+. The K currents in brown adipocytes activated with a sigmoidal delay after depolarizations to membrane potentials positive to -50 mV. Activation was half maximal at a potential of -28 mV and did not require the presence of significant concentrations of internal calcium. Maximal voltage-activated K conductance averaged 20 nS in high external K+ solutions. The K currents inactivated slowly with sustained depolarization with time constants for the inactivation process on the order of hundreds of milliseconds to tens of seconds. The K channels had an average single-channel conductance of 9 pS and a channel density of approximately 1,000 channels\/cell. The K current was blocked by tetraethylammonium or 4-aminopyridine with half maximal block occurring at concentrations of 1-2 mM for either blocker. K currents were unaffected by two blockers of Ca2+-activated K channels, charybdotoxin and apamin. Bath-applied norepinephrine did not affect the K currents or other membrane currents under our experimental conditions. These properties of the K channels indicate that they could produce an increase in the K+ permeability of the brown fat cell membrane during the depolarization that accompanies norepinephrine-stimulated thermogenesis, but that they do not contribute directly to the norepinephrine-induced depolarization.<\/jats:p>","DOI":"10.1085\/jgp.93.3.451","type":"journal-article","created":{"date-parts":[[2004,5,13]],"date-time":"2004-05-13T23:48:59Z","timestamp":1084492139000},"page":"451-472","update-policy":"https:\/\/doi.org\/10.1085\/jgp.crossmarkpolicy","source":"Crossref","is-referenced-by-count":35,"title":["Voltage-gated potassium channels in brown fat cells."],"prefix":"10.1085","volume":"93","author":[{"given":"M T","family":"Lucero","sequence":"first","affiliation":[{"name":"Department of Animal Physiology, University of California, Davis 95616."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P A","family":"Pappone","sequence":"additional","affiliation":[{"name":"Department of Animal Physiology, University of California, Davis 95616."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"291","published-online":{"date-parts":[[1989,3,1]]},"container-title":["The Journal of general physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/rupress.org\/jgp\/article-pdf\/93\/3\/451\/1813840\/451.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/rupress.org\/jgp\/article-pdf\/93\/3\/451\/1813840\/451.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,7,27]],"date-time":"2023-07-27T12:29:46Z","timestamp":1690460986000},"score":1,"resource":{"primary":{"URL":"https:\/\/rupress.org\/jgp\/article\/93\/3\/451\/27742\/Voltage-gated-potassium-channels-in-brown-fat"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1989,3,1]]},"references-count":0,"journal-issue":{"issue":"3","published-print":{"date-parts":[[1989,3,1]]}},"URL":"https:\/\/doi.org\/10.1085\/jgp.93.3.451","relation":{},"ISSN":["0022-1295","1540-7748"],"issn-type":[{"value":"0022-1295","type":"print"},{"value":"1540-7748","type":"electronic"}],"subject":[],"published":{"date-parts":[[1989,3,1]]}}}