{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T00:41:57Z","timestamp":1789432917737,"version":"build-2803163510"},"reference-count":0,"publisher":"Oxford University Press (OUP)","issue":"5","content-domain":{"domain":["eje.bioscientifica.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1997,5]]},"abstract":"<jats:title>Abstract<\/jats:title>\n        <jats:p>To study the effects of oxytocin on both spontaneous phasic contractions and K<jats:sup>+<\/jats:sup> outward currents (I<jats:sub>K<\/jats:sub>) of the so-called 'non-target' smooth muscle cells, physiological concentrations of oxytocin ranging between 10<jats:sup>\u221212<\/jats:sup> mol\/l and 10<jats:sup>\u22128<\/jats:sup> mol\/l were applied to smooth muscle preparations and single voltage-clamped cells isolated from the circular layer of the guinea-pig gastric antrum. Oxytocin (10<jats:sup>\u221212<\/jats:sup>mol\/l to 10<jats:sup>\u22128<\/jats:sup> mol\/l) suppressed, in a dose-dependent manner, the tetrodotoxin- and atropine-resistant spontaneous phasic contractions and shifted rightward the dose\u2013response curves of 10<jats:sup>\u22127<\/jats:sup> mol\/l charybdotoxin and 10<jats:sup>\u22123<\/jats:sup>mol\/l BaCl<jats:sub>2<\/jats:sub>. In cells with preloaded intracellular Ca<jats:sup>2+<\/jats:sup> stores, oxytocin (10<jats:sup>\u221212<\/jats:sup> mol\/l to 10<jats:sup>\u22129<\/jats:sup> mol\/l) caused a dose-dependent activation of the charybdotoxin-blockable non-inactivating component of I<jats:sub>K<\/jats:sub> (I<jats:sub>K(s1)<\/jats:sub>) of single voltage-clamped cells, which was accompanied by hyperpolarization of the cell membranes. <jats:sup>8<\/jats:sup>Lys-vasopressin and <jats:sup>8<\/jats:sup>arg-vasopressin failed to mimic the effects of oxytocin on both contraction and K<jats:sup>+<\/jats:sup> currents. Further, the oxytocin-induced activation of I<jats:sub>K(s1)<\/jats:sub> was effectively antagonized by 5\u00d7 10<jats:sup>\u22128<\/jats:sup> mol\/l U-73122 or 5\u00d7 10<jats:sup>\u22126<\/jats:sup> mol\/l 2-nitro-4-carboxyphenyl N,N-diphenylcarbamate (inhibitors of the cell membrane phospholipase C), as well as by intracellularly applied heparin (selective inhibitor of inositol-1,4,5-trisphosphate (IP<jats:sub>3<\/jats:sub>)-induced Ca<jats:sup>2+<\/jats:sup> release channels). In cells incubated in the absence of Ca<jats:sup>2+<\/jats:sup> entry throughout the study, oxytocin (10<jats:sup>\u22129<\/jats:sup> mol\/l) caused a slight and transient increase of I<jats:sub>K(s1)<\/jats:sub> amplitudes. Neither ryanodine (10<jats:sup>\u22126<\/jats:sup> mol\/l nor cyclopiazonic acid (10<jats:sup>\u22126<\/jats:sup> mol\/l) were able to restore the I<jats:sub>K<\/jats:sub>-activating effect of oxytocin in these cells.<\/jats:p>\n        <jats:p>The data obtained suggest (i) that selective oxytocin receptors are present on the membranes of guinea-pig antral smooth muscle cells, (ii) that the oxytocin-related relaxation may result from the activation of Ca<jats:sup>2+<\/jats:sup>-sensitive K<jats:sup>+<\/jats:sup> conductivity via activation of IP<jats:sub>3<\/jats:sub>-induced release of C<jats:sup>a<\/jats:sup> from the submembrane located cisternae of the sarcoplasmic reticulum Ca<jats:sup>2+<\/jats:sup> stores and (iii) in turn, this evokes a non-inactivating component of I<jats:sub>K<\/jats:sub>, hyperpolarizing the cell membrane.<\/jats:p>\n        <jats:p><jats:italic>European Journal of Endocrinology<\/jats:italic> <jats:bold>136<\/jats:bold> 531\u2013538<\/jats:p>","DOI":"10.1530\/eje.0.1360531","type":"journal-article","created":{"date-parts":[[2008,12,15]],"date-time":"2008-12-15T22:12:49Z","timestamp":1229379169000},"page":"531-538","update-policy":"https:\/\/doi.org\/10.1530\/crossmarkpolicy-1","source":"Crossref","is-referenced-by-count":23,"title":["Oxytocin-induced changes in single cell K+ currents and smooth muscle contraction of guinea-pig gastric antrum"],"prefix":"10.1093","volume":"136","author":[{"given":"Dessislava B","family":"Duridanova","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Milena D","family":"Nedelcheva","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hristo S","family":"Gagov","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","container-title":["European Journal of Endocrinology"],"original-title":[],"link":[{"URL":"https:\/\/eje.bioscientifica.com\/view\/journals\/eje\/136\/5\/eje_136_5_014.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/eje.bioscientifica.com\/view\/journals\/eje\/136\/5\/eje_136_5_014.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,2,14]],"date-time":"2023-02-14T16:23:42Z","timestamp":1676391822000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/ejendo\/article\/136\/5\/531\/6753702"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1997,5]]},"references-count":0,"journal-issue":{"issue":"5"},"URL":"https:\/\/doi.org\/10.1530\/eje.0.1360531","relation":{},"ISSN":["0804-4643","1479-683X"],"issn-type":[{"value":"0804-4643","type":"print"},{"value":"1479-683X","type":"electronic"}],"subject":[],"published":{"date-parts":[[1997,5]]}}}