| Autor: |
Stam, Hans, Geelhoed-Mieras, Tiny, Hülsmann, Willem |
| Zdroj: |
Lipids; Apr1980, Vol. 15 Issue 4, p242-250, 9p |
| Abstrakt: |
Male Wistar rats were fed for 3 or 10 days with high erucic acid rapeseed oil (HEAR) or trierucate (TE). These diets produced increased myocardial triglyceride (TG) levels. Cardiac lipid accumulation was related to basal-and hormone- (glucagon, norepinephrine) stimulated lipolysis, determined as glycerol release, which proved to be enhanced in isolated, perfused hearts from HEAR- and TE-fed rats. Endogenous TG levels in isolated hearts from rats fed the stock and the sunflowerseed oil (SSO) diet were low and probably rate-limiting for tissue lipolytic activities. HEAR feeding of rats did not modify the rate of erucic acid (22∶1) oxidation in heart. Prolonged HEAR and TE feeding led to a decrease in the endogenous TG level, a process in which the increased rate of TG hydrolysis might play an important role. The enhanced breakdown of tissue TG in hearts from TE-and HEAR-fed rats was accompanied by an increased release of fatty acids into the coronary effluent. Erucic acid was a major constituent of the perfusate fatty acids. Evidence is presented that the site of the intracellular TG breakdown is associated with lysosomes, since a subcellular fraction enriched in acid lipase, N-acetyl-β-glucosaminidase and TG could be isolated from heart homogenates of TE-fed rats. Fatty acids seemed to be an important regulator of tissue lipase activity: palmitate inhibited glucagon-stimulated lipolysis, which suggests the tissue lipase is subject to product inhibition by fatty acids. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
Full text from SpringerLink