{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,17]],"date-time":"2026-08-17T22:08:15Z","timestamp":1787004495665,"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":[[1977,10,15]]},"abstract":"<jats:p>1. Hepatic microsomal cytochrome P-450 concentrations are lower in selenium-deficient rats treated with phenobarbital for 4 days than in similarly treated control rats. 2. No defect in haem synthesis was found on the basis of measurements of delta-aminolaevulinate synthase (EC 2.3.1.37), delta-aminolaevulinate dehydratase (EC 4.2.1.24) and ferrochelatase (EC 4.99.1.1) activities, and urinary excretion of delta-aminolaevulinate, porphobilinogen, uroporphyrin and coproporphyrin. 3. No defect in apo-(cytochrome P-450) separated by sodium dodecyl sulphate\/polyacrylamide-gel electrophoresis. 4. An increase in haem catabolism was found. An 8-fold increase in hepatic microsomal haem oxygenase (EC 1.14.99.3) activity occurred in selenium-deficient rats after phenobarbital treatment, compared with a less than 2-fold increase in control rats. Also excretion of 14CO in the breath after administration of delta-amino[5-14C]laevulinate was greater by phenobarbital-treated selenium-deficient rats than by similarly treated controls. 5. These studies demonstrate that the defective induction of cytochrome P-450 by phenobarbital in selenium-deficient rats is accompanied by increased haem catabolism. This could be due to increased breakdown of cytochrome P-450 or to catabolism of haem before it attaches to the apo-cytochrome. The role of selenium in stabilizing cytochrome P-450 and\/or in protecting haem from breakdown remains to be determined.<\/jats:p>","DOI":"10.1042\/bj1680105","type":"journal-article","created":{"date-parts":[[2015,8,10]],"date-time":"2015-08-10T16:09:18Z","timestamp":1439222958000},"page":"105-111","update-policy":"https:\/\/doi.org\/10.1042\/crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Accelerated hepatic haem catabolism in the selenium-deficient rat"],"prefix":"10.1042","volume":"168","author":[{"given":"R F","family":"Burk","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M A","family":"Correia","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"288","container-title":["Biochemical Journal"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/168\/1\/105\/568743\/bj1680105.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/portlandpress.com\/biochemj\/article-pdf\/168\/1\/105\/568743\/bj1680105.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,11,26]],"date-time":"2021-11-26T12:35:08Z","timestamp":1637930108000},"score":1,"resource":{"primary":{"URL":"https:\/\/portlandpress.com\/biochemj\/article\/168\/1\/105\/11255\/Accelerated-hepatic-haem-catabolism-in-the"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1977,10,15]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1977,10,15]]}},"URL":"https:\/\/doi.org\/10.1042\/bj1680105","relation":{},"ISSN":["0264-6021"],"issn-type":[{"value":"0264-6021","type":"print"}],"subject":[],"published":{"date-parts":[[1977,10,15]]}}}