Involvement of protein kinase C in Ca(2+)-independent contraction of rat uterine smooth muscle.
The contribution of protein kinase C to the contraction by oxytocin of rat uterine longitudinal smooth muscle in Ca(2+)-free solution was investigated. Immunological analysis revealed that type II (beta) and III (alpha) protein kinase C subspecies were present in rat uterine smooth muscle. The pretreatment of a diacylglycerol kinase inhibitor R59022 to accumulate diacylglycerol potentiated the Ca(2+)-independent contraction. The contractile activity was diminished with the depletion of protein kinase C, when the contraction was evoked repeatedly by oxytocin during the prolonged exposure to a tumor-promoting phorbol ester 12-O-tetradecanoylphorbol 13-acetate. These results suggested the involvement of protein kinase C in oxytocin-induced contraction in Ca(2+)-free solution.
Karibe
H
H
Department of Molecular Pharmacology, Meiji College of Pharmacy, Tokyo, Japan.
Oishi
K
K
Uchida
M K
MK
D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000201:enzymology; D002118:Calcium / Q000494:pharmacology*; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D066298:In Vitro Techniques; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism*; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D010121:Oxytocin / Q000494:pharmacology*; D011493:Protein Kinase C / Q000302:isolation & purification / Q000378:metabolism*; D011744:Pyrimidinones / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013844:Thiazoles / Q000494:pharmacology; D014599:Uterus / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*
D007527:Isoenzymes; D011744:Pyrimidinones; D013844:Thiazoles; D010121:Oxytocin; C047505:R 59022; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium