EFFECTS OF ADRENERGIC AGONISTS AND ANTAGONISTS ON THE METABOLISM OF [1-C-14]OLEIC ACID BY RAT HEPATOCYTES

Citation
Jo. Olubadewo et M. Heimberg, EFFECTS OF ADRENERGIC AGONISTS AND ANTAGONISTS ON THE METABOLISM OF [1-C-14]OLEIC ACID BY RAT HEPATOCYTES, Biochemical pharmacology, 45(12), 1993, pp. 2441-2447
Citations number
45
Categorie Soggetti
Pharmacology & Pharmacy",Biology
Journal title
ISSN journal
00062952
Volume
45
Issue
12
Year of publication
1993
Pages
2441 - 2447
Database
ISI
SICI code
0006-2952(1993)45:12<2441:EOAAAA>2.0.ZU;2-D
Abstract
The possibility that the antihypertensive adrenoceptor antagonists (pr opranolol, phentolamine and metoprolol) may alter hepatic lipid metabo lism was examined in freshly dispersed rat hepatocytes with [1-C-14]ol eate. Propranolol (1.8 x 10(-4) M) and phentolamine (1.4 x 10(-4) M) i ncreased incorporation of [1-C-14]oleate into cholesteryl esters by 51 and 92%, respectively, and decreased ketogenesis by 46 and 62%, respe ctively. While neither drug affected incorporation into total phosphol ipid, propranolol decreased triglyceride synthesis by 37%. These effec ts of propranolol and phentolamine may not occur through beta- or alph a-receptor inhibition since neither epinephrine nor norepinephrine rev ersed the effects of the adrenoceptor antagonists. Although epinephrin e and norepinephrine per se did not alter the incorporation of [1-C-14 ]oleate into triglyceride, phospholipid, cholesteryl esters or ketone bodies, they stimulated the production of (CO2)-C-14 (control 5.6 +/- 1.3; epinephrine 7.6 +/- 1.1; norepinephrine 9.1 +/- 0.2 nmol oleate i ncorporated/mg protein), and these effects were reversed by phentolami ne and propanolol. The data suggest that adrenoceptor antagonists exer t direct effects on hepatic metabolism of oleate.