{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,20]],"date-time":"2025-10-20T18:35:40Z","timestamp":1760985340258},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"2","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1983,2,15]]},"abstract":"<jats:p>Electrothermal atomic-absorption spectroscopy was employed for measuring manganese in beta-cell-rich pancreatic islets isolated from ob\/ob mice. The efflux from preloaded islets was estimated from the amounts remaining after 30 min of subsequent test incubations in the absence of Mn2+. An increase in the extracellular Mg2+ concentration promoted the Mn2+ efflux and removal of Na+ from a Ca2+-deficient medium had the opposite effect. Addition of 25 mM-K+ failed to affect Mn2+ outflow as did 3-isobutyl-1-methylxanthine and dibutyryl cyclic AMP. Whereas tolbutamide caused retention of manganese, the ionophore Br-X537A promoted an efflux. D-Glucose was equally potent in retaining the islet manganese when the external Ca2+ concentration ranged from 15 microM to 6.30 mM. Subcellular-fractionation experiments indicated a glucose-stimulated incorporation of manganese into all fractions except the microsomes. The effect was most pronounced in the mitochondrial fraction, being as high as 164%. The glucose-induced uptake of intracellular 45Ca was abolished in the presence of 0.25 mM-Mn2+. When added to medium containing 2.5 mM-Mn2+, glucose even tended to decrease 45Ca2+ uptake. The inhibitory effect of Mn2+ was apparent also from a diminished uptake of 45Ca into all subcellular fractions. The efflux of 45Ca2+ was markedly influenced by Mn2+ as manifested in a prominent stimulation followed by inhibition. In addition to demonstrating marked interactions between fluxes of Mn2+ and Ca2+, the present studies support the view that the glucose inhibition of the efflux of bivalent cations from pancreatic beta-cells is accounted for by their accumulation in the mitochondria.<\/jats:p>","DOI":"10.1042\/bj2100307","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T20:36:13Z","timestamp":1439238973000},"page":"307-314","update-policy":"http:\/\/dx.doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["The interaction between manganese and calcium fluxes in pancreatic \u03b2-cells"],"prefix":"10.1042","volume":"210","author":[{"given":"P","family":"Rorsman","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"B","family":"Hellman","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/210\/2\/307\/784841\/bj2100307.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/210\/2\/307\/784841\/bj2100307.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,25]],"date-time":"2021-11-25T13:08:13Z","timestamp":1637845693000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/210\/2\/307\/14597\/The-interaction-between-manganese-and-calcium"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1983,2,15]]},"references-count":0,"journal-issue":{"issue":"2","published-print":{"date-parts":[[1983,2,15]]}},"URL":"https:\/\/doi.org\/10.1042\/bj2100307","relation":{},"ISSN":["0306-3283"],"issn-type":[{"value":"0306-3283","type":"print"}],"subject":[],"published":{"date-parts":[[1983,2,15]]}}}