@article {Guthrie621, author = {T S Guthrie and J Tsuji and J N Wells}, title = {A synthetic pseudosubstrate peptide of protein kinase C inhibits the phorbol-12,13-dibutyrate effect on permeabilized coronary artery smooth muscle.}, volume = {39}, number = {5}, pages = {621--624}, year = {1991}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {We have studied the effects of a synthetic peptide that is based on the autoinhibitory domain of protein kinase C on tension development in detergent-permeabilized coronary artery smooth muscle. This peptide inhibited two forms of protein kinase C that were isolated from the coronary artery media layer by hydroxylapatite chromatography, with apparent Ki values in the 5-8 microM range. Contractions induced by calcium in the permeabilized arteries were not affected by the peptide (30 microM). Potentiation of calcium-induced contractions by 1 microM phorbol-12,13-dibutyrate was partially inhibited by 10 microM peptide and was completely abolished by 30 microM peptide. These results indicate that phorbol-12,13-dibutyrate potentiates calcium-induced contractions of permeabilized coronary arteries by activation of protein kinase C, but activated protein kinase C is not a requirement for the induction of contractions by calcium alone.}, issn = {0026-895X}, URL = {https://molpharm.aspetjournals.org/content/39/5/621}, eprint = {https://molpharm.aspetjournals.org/content/39/5/621.full.pdf}, journal = {Molecular Pharmacology} }