Short-term incubation of cardiac myocytes with isoprenaline has no effect on heparin-releasable or cellular lipoprotein lipase activity.
Heparin (5 units/ml) produced a rapid (5-10 min) release of lipoprotein lipase (LPL) into the incubation medium of cardiac myocytes. Preincubation of myocytes for 30 min with 0.01-10 microM-isoprenaline, 100 microM-forskolin or 500 microM-8-(4-chlorophenylthio)adenosine 3',5'-cyclic monophosphate did not increase heparin-releasable LPL activity. Incubation with isoprenaline also did not change cellular LPL activity, even though the catecholamine did increase the phosphorylase a activity ratio.
Severson
D L
DL
Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Calgary, Alberta, Canada.
Carroll
R
R
Kryski
A
A
Ramírez
I
I
D000818:Animals; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D006321:Heart / Q000187:drug effects; D006493:Heparin / Q000493:pharmacokinetics / Q000494:pharmacology*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology*; D008071:Lipoprotein Lipase / Q000378:metabolism*; D008297:Male; D009206:Myocardium / Q000166:cytology / Q000378:metabolism*; D010762:Phosphorylase a / Q000378:metabolism; D051381:Rats
D005576:Colforsin; D006493:Heparin; D000242:Cyclic AMP; D010762:Phosphorylase a; D008071:Lipoprotein Lipase; D007545:Isoproterenol