title: Protein kinase C activity and contractile responsiveness in senescent blood vessels.
abstract: To examine Ca2(+)-signaling receptor function in the aging vasculature, the status of the diacylglycerol/protein kinase C (DAG/PKC) arm of the signal transduction pathway was assessed. contractile responsiveness to the PKC activator, phorbol 12-myristate 13-acetate (PMA), is substantially reduced in aortae from 24-month-old Fischer 344 rats compared to 6-month-old rats. PKC activity is reduced in all senescent vessels yet studied including aorta, renal artery, iliac artery and vena cava. This may account for the reduced contractile responsiveness. Additionally, PMA-stimulated PKC translocation is substantially reduced in senescent aorta and this may also contribute to reduced contraction.
authors.affiliation: Department of Pharmacology, Medical College of Pennsylvania, Philadelphia 19129.
authors.forename: M D
authors.initials: MD
authors.lastname: Johnson
authors.forename: H Y
authors.initials: HY
authors.lastname: Wang
authors.forename: E
authors.initials: E
authors.lastname: Friedman
mesh_terms: D000375:Aging / Q000502:physiology; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects / Q000378:metabolism; D002540:Cerebral Cortex / Q000254:growth & development / Q000502:physiology; D004075:Diglycerides / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000201:enzymology* / Q000502:physiology; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D015398:Signal Transduction / Q000502:physiology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D004075:Diglycerides; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate