Differential recovery of protein kinase C-alpha and -epsilon isozymes after long-term phorbol ester treatment in rat renal mesangial cells.
Glomerular mesangial cells have been shown to express two protein kinase C (PKC) isozymes, PKC-alpha and PKC-epsilon. Upon long-term treatment with phorbol ester PKC-alpha is depleted faster than PKC-epsilon. Here we demonstrate that removal of phorbol ester results in a differential recovery of PKC-alpha and -epsilon isozymes. Whereas PKC-epsilon starts to recover within 1h, PKC-alpha does not begin to recover before 4 h after removal of phorbol ester. These data suggest a differential rate of protein synthesis of PKC-alpha and -epsilon. In parallel to the recovery of PKC isozymes mesangial cells also regained their functional responsiveness, i.e., stimulation of prostaglandin synthesis and feedback inhibition of angiotensin II-stimulated InsP3 formation.
Huwiler
A
A
Research Department, Ciba-Geigy Ltd, Basel, Switzerland.
Fabbro
D
D
Pfeilschifter
J
J
D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D015232:Dinoprostone / Q000096:biosynthesis; D005920:Glomerular Mesangium / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D015151:Immunoblotting; D007295:Inositol Phosphates / Q000378:metabolism; D007527:Isoenzymes / Q000378:metabolism*; D007700:Kinetics; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology*; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats
D007295:Inositol Phosphates; D007527:Isoenzymes; D000804:Angiotensin II; D015240:Phorbol 12,13-Dibutyrate; D011493:Protein Kinase C; D015232:Dinoprostone