{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,1,14]],"date-time":"2024-01-14T10:12:57Z","timestamp":1705227177033},"reference-count":0,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[1982,2,1]],"date-time":"1982-02-01T00:00:00Z","timestamp":381369600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["The Journal of Physiology"],"published-print":{"date-parts":[[1982,2]]},"abstract":"<jats:p>1. The unfertilized egg of an ascidian, <jats:italic>Halocynthia roretzi<\/jats:italic>, was activated by the divalent ionophore A23187 in natural or artificial sea water (nSW or ASW) or by an external solution containing a high concentration of Ca ions (high\u2010Ca ASW) under voltage\u2010clamp condition.<\/jats:p><jats:p>2. Activation current began with an abrupt increase in the holding current and decayed relatively slowly with a common time course in various ASWs. Activation current was both Na\u2010 and Ca\u2010dependent. The peak time, <jats:italic>T<\/jats:italic><jats:sub>p<\/jats:sub>, and the peak amplitude, <jats:italic>D<\/jats:italic>, of the activation current in nSW at 15 \u00b0C and \u201090 mV were 27 \u00b1 4 sec and \u20101\u00b750 \u00b1 0\u00b747 nA, respectively.<\/jats:p><jats:p>3. The currents through Na, Ca and anomalous K channels were evoked by test pulses with constant intervals in nSW and high\u2010Sr, high\u2010Ca and high\u2010K ASWs. Na\u2010channel current was enhanced during activation. In contrast, Ca\u2010channel current decreased. In high\u2010Ca, Na\u2010free ASW the Ca current through Na channels increased while the Ca current through Ca channels decreased. The time for the maximum of Na current, <jats:italic>T<\/jats:italic><jats:sub>max<\/jats:sub>, was (7\u00b72 \u00b1 1\u00b75) \u00d7 10 sec at 15 \u00b0C and index <jats:italic>R<\/jats:italic>, the ratio of the maximum amplitude to the amplitude before activation, was 2\u00b731 \u00b1 0\u00b718 in nSW. The time for the minimum of Ca\u2010channel current, <jats:italic>T<\/jats:italic><jats:sub>min<\/jats:sub>, was about 70 sec, being almost the same as <jats:italic>T<\/jats:italic><jats:sub>max<\/jats:sub> of Na current.<\/jats:p><jats:p>4. The current through anomalous K channels increased initially and decreased later with a time lag behind the decrease in Ca\u2010channel current.<\/jats:p><jats:p>5. Both <jats:italic>T<\/jats:italic><jats:sub>p<\/jats:sub> of activation current and <jats:italic>T<\/jats:italic><jats:sub>max<\/jats:sub> of Na current were reduced by raising the temperature. <jats:italic>Q<\/jats:italic><jats:sub>10<\/jats:sub> for <jats:italic>T<\/jats:italic><jats:sub>p<\/jats:sub> and <jats:italic>T<\/jats:italic><jats:sub>max<\/jats:sub> was 2\u00b72 and 2\u00b73, respectively.<\/jats:p><jats:p>6. When the egg was activated in ASW containing scorpion toxin, the Na current through normal channels increased strongly while the Na current through toxinmodified channels increased less markedly.<\/jats:p><jats:p>7. There was no significant change in the total membrane capacity before and during activation.<\/jats:p>","DOI":"10.1113\/jphysiol.1982.sp014072","type":"journal-article","created":{"date-parts":[[2014,12,19]],"date-time":"2014-12-19T07:05:22Z","timestamp":1418972722000},"page":"267-286","source":"Crossref","is-referenced-by-count":20,"title":["Changes in holding and ion\u2010channel currents during activation of an ascidian egg under voltage clamp"],"prefix":"10.1113","volume":"323","author":[{"given":"Masao","family":"Kozuka","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kunitaro","family":"Takahashi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"311","published-online":{"date-parts":[[1982,2]]},"container-title":["The Journal of Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1113%2Fjphysiol.1982.sp014072","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/pdf\/10.1113\/jphysiol.1982.sp014072","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,11,6]],"date-time":"2023-11-06T04:47:30Z","timestamp":1699246050000},"score":1,"resource":{"primary":{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/10.1113\/jphysiol.1982.sp014072"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1982,2]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1982,2]]}},"alternative-id":["10.1113\/jphysiol.1982.sp014072"],"URL":"https:\/\/doi.org\/10.1113\/jphysiol.1982.sp014072","archive":["Portico"],"relation":{},"ISSN":["0022-3751","1469-7793"],"issn-type":[{"value":"0022-3751","type":"print"},{"value":"1469-7793","type":"electronic"}],"subject":[],"published":{"date-parts":[[1982,2]]}}}