title: Regulation of mitogen-activated protein kinase by protein kinase C and mitogen-activated protein kinase phosphatase-1 in vascular smooth muscle.
abstract: Vascular smooth muscle contraction is primarily regulated by phosphorylation of myosin light chain. There are also modulatory pathways that control the final level of force development. We tested the hypothesis that protein kinase C (PKC) and mitogen-activated protein (MAP) kinase modulate vascular smooth muscle activity via effects on MAP kinase phosphatase-1 (MKP-1). Swine carotid arteries were mounted for isometric force recording and subjected to histamine stimulation in the presence and absence of inhibitors of PKC [bisindolylmaleimide-1 (Bis)], MAP kinase kinase (MEK) (U0126), and MKP-1 (sanguinarine) and flash frozen for measurement of MAP kinase, PKC-potentiated myosin phosphatase inhibitor 17 (CPI-17), and caldesmon phosphorylation levels. CPI-17 was phosphorylated in response to histamine and was inhibited in the presence of Bis. Caldesmon phosphorylation levels increased in response to histamine stimulation and were decreased in response to MEK inhibition but were not affected by the addition of Bis. Inhibition of PKC significantly increased p42 MAP kinase, but not p44 MAP kinase. Inhibition of MEK with U0126 inhibited both p42 and p44 MAP kinase activity. Inhibition of MKP-1 with sanguinarine blocked the Bis-dependent increase of MAP kinase activity. Sanguinarine alone increased MAP kinase activity due to its effects on MKP-1. Sanguinarine increased MKP-1 phosphorylation, which was inhibited by inhibition of MAP kinase. This suggests that MAP kinase has a negative feedback role in inhibiting MKP-1 activity. Therefore, PKC catalyzes MKP-1 phosphorylation, which is reversed by MAP kinase. Thus the fine tuning of vascular contraction is due to the concerted effort of PKC, MAP kinase, and MKP-1.
authors.affiliation: Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania; Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania; and.
authors.forename: Danielle M
authors.initials: DM
authors.lastname: Trappanese
authors.affiliation: Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania;
authors.forename: Sarah
authors.initials: S
authors.lastname: Sivilich
authors.affiliation: Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania;
authors.forename: Hillevi K
authors.initials: HK
authors.lastname: Ets
authors.affiliation: Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania; and.
authors.forename: Farah
authors.initials: F
authors.lastname: Kako
authors.affiliation: Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, Pennsylvania; and.
authors.forename: Michael V
authors.initials: MV
authors.lastname: Autieri
authors.affiliation: Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, Pennsylvania; Department of Pathology and Laboratory Medicine, Drexel University College of Medicine, Philadelphia, Pennsylvania robert.moreland@drexelmed.edu.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Moreland
mesh_terms: D000818:Animals; D002148:Calmodulin-Binding Proteins / Q000378:metabolism; D002339:Carotid Arteries / Q000201:enzymology; D054638:Dual Specificity Phosphatase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D025461:Feedback, Physiological; D066298:In Vitro Techniques; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000201:enzymology*; D010766:Phosphorylation; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D015398:Signal Transduction; D013552:Swine; D014661:Vasoconstriction / Q000187:drug effects; D014662:Vasoconstrictor Agents / Q000494:pharmacology
chemical_list: D002148:Calmodulin-Binding Proteins; D047428:Protein Kinase Inhibitors; D014662:Vasoconstrictor Agents; D011493:Protein Kinase C; D019950:Mitogen-Activated Protein Kinase 1; D054638:Dual Specificity Phosphatase 1
keywords: CPI-17; U0126; bisindolylmaleimide-1; caldesmon; phos-tag gel electrophoresis; sanguinarine