Metabolic responsiveness to phorbol ester and activity of protein kinase C in isolated hepatocytes from partially hepatectomized rats.
The ability of isolated rat hepatocytes to respond to phorbol-12-myristate-13-acetate (PMA) with acute stimulation of de novo fatty acid synthesis was markedly depressed at 4, 22 and 48 h after partial hepatectomy (PH). This desensitization was not due to surgical stress as shown by comparison with hepatocytes from sham-operated animals. Moreover, the total activity of protein kinase C (PK-C), the principal phorbol ester receptor, was not down-regulated at 22 h after partial hepatectomy. Partial hepatectomy rather caused a small but distinct shift in subcellular PK-C distribution toward the particulate fraction thereby suggesting a modest activation of PK-C. We conclude that the PH-induced desensitization to PMA occurs at a point beyond PK-C activation.
Houweling
M
M
Laboratory of Veterinary Biochemistry, State University of Utrecht, The Netherlands.
Vaartjes
W J
WJ
van Golde
L M
LM
D000103:Acetyl-CoA Carboxylase / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D004261:DNA Replication; D005227:Fatty Acids / Q000096:biosynthesis*; D006498:Hepatectomy; D008025:Ligases / Q000378:metabolism*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008115:Liver Regeneration; D008297:Male; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D013347:Subcellular Fractions / Q000201:enzymology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
D005227:Fatty Acids; D011493:Protein Kinase C; D008025:Ligases; D000103:Acetyl-CoA Carboxylase; D013755:Tetradecanoylphorbol Acetate