Mitogen Activated Protein Kinases

MAP kinases participate in signal transduction classically associated with cell proliferation, differentiation, and death.l02 Of the major mammalian MAP kinases, ERKl/2, p38 MAP kinase, and JNK are the best characterized. ERKl/2, phosphorylated by MEKl/2 (MAP/ERK kinase), is a key growth signaling kinase, whereas JNK and p38 MAP kinase, phosphorylated by MEK4/7 and MEK3/6, respectively, influence cell survival, apoptosis, differentiation, and inflammation.l()2 ERK5, a recently identified MAP kinase, is regulated by MEK5 and is involved in protein synthesis, cell cycle progression, and cell growth^02 Enhanced activation of vascular MAP kinases has been demonstrated in hypertension and seems to be a major mechanism contributing to vascular damage in hypertension.l03l(4 MAP kinases are regulated by phosphorylation cascades^02 In addition these kinases are activated by ROS or by a mild oxidative shift of the intracellular thiol/disulfide redox stated05 In VSMCs intracellular ROS are critical for Ang II-induced activation of p38MAPK, JNK, and ERK5, whereas phosphorylation of ERKl/2 appears to be redox-insensi-tive.l06l(7 However, serotonin-mediated ERKl/2 activation in smooth muscle cells is redox-sensitive, but in fibroblasts, it is not,l0!i suggesting that redox-regulation of MAP kinases may be ligand- and cell-specific. Although MAP kinases are influenced by free radicals, they are probably not direct substrates of ¬ĽO2- and H2O2. Upstream modulators such as MEKs, tyrosine kinases, and phosphatases may be direct targets.

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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