Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1992-10-20
pubmed:abstractText
A 3'-methyl-4-dimethylaminoazobenzene (3'-MeDAB) containing diet was given to 6 weeks old female Donryu rats, and the number of adrenoceptors and the response of adenylate cyclase in the hepatocytes were measured. The treatment with 3'-MeDAB led to rapid increases in [125I]iodocyanopindolol ([125I]ICYP)- and [3H]clonidine-binding sites to hepatic membranes without significant changes in the Kd values. The number or beta-adrenoceptors defined by [125I]ICYP binding sites was increased with a biphagic mode. The [3H]clonidine binding reached a peak 2 weeks after the start of the carcinogen diet and then began a slow descent. The alpha 2-adrenoceptor was defined by [3H]clonidine binding being selectively inhibited by an alpha 2-antagonist, yohimbine, but not by an alpha 1-antagonist, prazosin, or a beta-antagonist propranolol. Catecholamine responsiveness to adenylate cyclase in hepatocytes also increased during treatment with 3'-MeDAB. However, the efficacy of norepinephrine (NE) in activating cyclase was lower than that of isoproterenol (IPN) during 4 to 8 weeks of the carcinogen diet. The difference between the efficacies of IPN and NE resulted from inhibiting adenylate cyclase through alpha 2-adrenoceptors by NE. Therefore, we noticed that the increasing pattern of the number of beta-adrenoceptors did not always parallel IPN-stimulated adenylate cyclase activity and that the increase in the number of alpha 2-adrenoceptors preceded the difference between the efficacies of IPN and NE in activating adenylate cyclase.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0386-846X
pubmed:author
pubmed:issnType
Print
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
247-54
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Changes in alpha 2- and beta-adrenoceptors in hepatocytes from rats during treatment with 3'-methyl-4-dimethylaminoazobenzene.
pubmed:affiliation
Research Laboratory for Development of Medicine, School of Pharmacy, Hokuriku University, Kanazawa, Japan.
pubmed:publicationType
Journal Article, In Vitro