title: Effect of phorbol esters on the distribution and total activity of protein kinase C in the perfused rat heart.
abstract: 1. The perfused rat heart was treated with the tumour-promoter and protein kinase C activator, phorbol 12-myristate 13-acetate and the distribution of protein kinase C activity between cytosolic and particulate fractions determined. 2. Phorbol ester treatment led to a rapid loss of protein kinase C activity from the cytosol (t0.5 = 2 min) with a corresponding translocation into the particulate fraction. Translocated protein kinase C activity was tightly bound to the particulate fraction, could only be extracted with buffers containing 2% Triton X-100 and could therefore be misinterpreted as being down-regulated. 3. Claims of rapid down-regulation of protein kinase C activity by phorbol esters need to be supported by rigorous procedures for extraction of the particulate material.
authors.affiliation: Department of Biochemistry, University of Tasmania, Australia.
authors.forename: S
authors.initials: S
authors.lastname: Rattigan
authors.forename: A G
authors.initials: AG
authors.lastname: Davison
authors.forename: P J
authors.initials: PJ
authors.lastname: Cleland
authors.forename: M G
authors.initials: MG
authors.lastname: Clark
mesh_terms: D000818:Animals; D003600:Cytosol / Q000201:enzymology; D015536:Down-Regulation; D006321:Heart / Q000187:drug effects*; D008297:Male; D009206:Myocardium / Q000201:enzymology; D010477:Perfusion; D011493:Protein Kinase C / Q000302:isolation & purification / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate