Inhibition of protein kinase C activity and vascular smooth muscle cell growth by d-alpha-tocopherol.
The inhibition by d-alpha-tocopherol of protein kinase C activity has been studied in synchronised A7r5 rat smooth muscle cells during the cell cycle. Cell protein kinase C activity has been found to oscillate, with a minimum in the G0 phase, a maximum in the late G1 phase and a new minimum in the S phase. An inhibition of protein kinase C activity by d-alpha-tocopherol appears to be at the basis of cell growth inhibition. Nevertheless, the amount of the different protein kinase C isoenzymes present in smooth muscle cells, measured by their specific antibodies, does not change during the cell cycle in both untreated and d-alpha-tocopherol-treated cells. The possible mechanisms of protein kinase C modulation during the cell cycle and of its inhibition by d-alpha-tocopherol are discussed.
Boscoboinik
D O
DO
Institut für Biochemie und Molekularbiologie, Universität Bern, Switzerland.
Chatelain
E
E
Bartoli
G M
GM
Stäuble
B
B
Azzi
A
A
D000818:Animals; D002453:Cell Cycle; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D051381:Rats; D014810:Vitamin E / Q000494:pharmacology*
D014810:Vitamin E; D004247:DNA; D011493:Protein Kinase C