{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T10:03:36Z","timestamp":1791194616810,"version":"4.1.0"},"reference-count":0,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"6","license":[{"start":{"date-parts":[[2015,9,1]],"date-time":"2015-09-01T00:00:00Z","timestamp":1441065600000},"content-version":"tdm","delay-in-days":6666,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1997,6]]},"abstract":"<jats:sec>\n            <jats:title\/>\n            <jats:p>Acetaminophen (N-acetyl-p-aminophenol [APAP]) hepatotoxicity is a process characterized by Ca<jats:sup>2+<\/jats:sup> deregulation. Cellular functions utilizing Ca<jats:sup>2+<\/jats:sup> as a second messenger molecule affect both cytosolic and nuclear signal transduction. Many studies have independently shown Ca<jats:sup>2+<\/jats:sup>- related effects on target molecules in response to toxic doses of APAP; however, the primary Ca<jats:sup>2+<\/jats:sup> target resulting in liver necrosis has not been determined. We hypothesize that Ca<jats:sup>2+<\/jats:sup>-dependent DNA damage is a critical event in liver necrosis caused by alkylating hepatotoxins. In this study, Ca<jats:sup>2+<\/jats:sup>-dependent endonuclease activity was determined from DNA single-strand lesions measured by fluorometric analysis of DNA unwinding. The status of cytosolic Ca<jats:sup>2+<\/jats:sup> was determined by measuring Ca<jats:sup>2+<\/jats:sup>-dependent activation of glycogen phosphorylase a. Primary cultures of mouse hepatocytes exposed to a toxic concentration of APAP showed twofold and greater increases in glycogen phosphorylase a stimulation at 6 hours, which was reversible with Ca<jats:sup>2+<\/jats:sup>-chelating agents. Cell death was preceded by a large decline in intact, double-stranded DNA. Following toxic administration of APAP, the percentage of total double- stranded DNA was significantly reduced by 2 hours. At 6 and 24 hours, genomic integrity was compromised by 26% and 37%, respectively, compared with untreated controls. Hepatotoxic effects of APAP-mediated Ca<jats:sup>2+<\/jats:sup> deregulation were confirmed in both primary mouse hepatocytes and the human hepatoblastoma HepG2 cell line by lactate dehydrogenase (LDH) release and tetrazolium reduction using the 3-4,5-dimethylthiazole-2-yl- 2,5-diphenyltetrazolium bromide thiazol blue(MTT) assay. The Ca<jats:sup>2+<\/jats:sup> chelator, ethylene glycol-bis (\u03b2-aminoethyl ether) <jats:italic toggle=\"yes\">N<\/jats:italic>\u2032,<jats:italic toggle=\"yes\">N<\/jats:italic>\u2032,<jats:italic toggle=\"yes\">N<\/jats:italic>\u2032, <jats:italic toggle=\"yes\">N<\/jats:italic>\u2032- tetraacetic acid (EGTA), blocked APAP-induced phosphorylase a activation and necrotic cell death, but failed to inhibit phosphorylase a activation by the adenosine 3\u2032,5\u2032-cyclic monophosphate (cAMP) analogue, dibutyryl cAMP, indicating little or no contribution of the cAMP pathway to phosphorylase a stimulation during APAP-induced necrotic death. Results with these in vitro models of liver injury are interpreted as supporting the hypothesis that increased Ca<jats:sup>2+<\/jats:sup> availability plays a major role in the progression of APAP-dependent cellular necrosis, and that the nucleus is a critical target for APAP hepatotoxicity.<\/jats:p>\n          <\/jats:sec>","DOI":"10.1002\/hep.510250621","type":"journal-article","created":{"date-parts":[[2004,7,27]],"date-time":"2004-07-27T23:06:43Z","timestamp":1090969603000},"page":"1432-1438","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":38,"title":["Calcium-dependent DNA damage and adenosine 3\u2032,5\u2032-cyclic monophosphate- independent glycogen phosphorylase activation in an in vitro model of acetaminophen-induced liver injury"],"prefix":"10.1097","volume":"25","author":[{"given":"V M","family":"Salas","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"G B","family":"Corcoran","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","container-title":["Hepatology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fhep.510250621","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.lww.com\/01515467-199706000-00022","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,2,7]],"date-time":"2025-02-07T15:27:48Z","timestamp":1738942068000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.lww.com\/01515467-199706000-00022"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1997,6]]},"references-count":0,"journal-issue":{"issue":"6","published-print":{"date-parts":[[1997]]}},"URL":"https:\/\/doi.org\/10.1002\/hep.510250621","relation":{},"ISSN":["0270-9139"],"issn-type":[{"value":"0270-9139","type":"print"}],"subject":[],"published":{"date-parts":[[1997,6]]}}}