{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T15:40:58Z","timestamp":1787067658998,"version":"build-2736575974"},"reference-count":0,"publisher":"Portland Press Ltd.","issue":"1","content-domain":{"domain":["portlandpress.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[1992,8,15]]},"abstract":"<jats:p>Pyrazole, cobalt and phenobarbital increase the activity of coumarin 7-hydroxylase (COH) in mouse liver. To study the mechanism of this increase, we measured the expression of the cytochrome P-450 2a-4\/5 (Cyp2a-4\/5) complex, which mediates testosterone 15 alpha-hydroxylase and COH activities, as a function of dose and time after the treatment of C57BL\/6 (B6) and DBA\/2 (D2) male mice with the inducers. COH activity and Cyp2a-4\/5 steady-state mRNA levels were increased in both strains in response to the inducers. No marked effect occurred with testosterone 15 alpha-hydroxylase or activities associated with Cyp1a-1 or Cyp2e-1. A 2-7-fold increase in response to the inducers was seen in the amount of P-450Coh (cytochrome P-450 isoenzyme catalysing coumarin 7-hydroxylation) protein in Western immunoblots. PCR amplification of a 1 kb region in Cyp2a-4\/5-mRNA-derived cDNA, followed by cutting at the diagnostic PstI site, showed that most of the steady-state mRNA consisted of Cyp2a-5, which is also the form most affected by pyrazole. Nuclear run-off analysis revealed no increase in the transcription rate of Cyp2a-4\/5 after pyrazole or cobalt treatment, whereas a 2-3-fold increase occurred after phenobarbital pretreatment in B6 mice. Together with previous reports [Aida &amp; Negishi (1991) Biochemistry 30, 8041-8045], the current data suggest that both pyrazole and cobalt increase COH catalytic activity by affecting Cyp2a-5 by post-transcriptional mechanisms in mice.<\/jats:p>","DOI":"10.1042\/bj2860289","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T17:28:42Z","timestamp":1439227722000},"page":"289-294","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["Effect of pyrazole, cobalt and phenobarbital on mouse liver cytochrome\n                    <i>P<\/i>\n                    -450 2a-4\/5 (Cyp2a-4\/5) expression"],"prefix":"10.1042","volume":"286","author":[{"given":"B","family":"Hahnemann","sequence":"first","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Oulu, SF-90220 Oulu, Finland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P","family":"Salonp\u00e4\u00e4","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Oulu, SF-90220 Oulu, Finland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M","family":"Pasanen","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Oulu, SF-90220 Oulu, Finland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J","family":"M\u00e4enp\u00e4\u00e4","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Oulu, SF-90220 Oulu, Finland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P","family":"Honkakoski","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Kuopio, SF-70220 Kuopio, Finland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R","family":"Juvonen","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Kuopio, SF-70220 Kuopio, Finland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M A","family":"Lang","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Kuopio, SF-70220 Kuopio, Finland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"O","family":"Pelkonen","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Oulu, SF-90220 Oulu, Finland."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"H","family":"Raunio","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, University of Oulu, SF-90220 Oulu, Finland."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/286\/1\/289\/607325\/bj2860289.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/286\/1\/289\/607325\/bj2860289.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,23]],"date-time":"2021-11-23T16:46:24Z","timestamp":1637685984000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/286\/1\/289\/27704\/Effect-of-pyrazole-cobalt-and-phenobarbital-on"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1992,8,15]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1992,8,15]]}},"URL":"https:\/\/doi.org\/10.1042\/bj2860289","relation":{},"ISSN":["0264-6021","1470-8728"],"issn-type":[{"value":"0264-6021","type":"print"},{"value":"1470-8728","type":"electronic"}],"subject":[],"published":{"date-parts":[[1992,8,15]]}}}