94 research outputs found
Losartan Decreases p42/44 MAPK Signaling and Preserves LZ+ MYPT1 Expression
Heart failure is associated with impairment in nitric oxide (NO) mediated vasodilatation, which has been demonstrated to result from a reduction in the relative expression of the leucine zipper positive (LZ+) isoform of the myosin targeting subunit (MYPT1) of myosin light chain phosphatase. Further, captopril preserves normal LZ+ MYPT1 expression, the sensitivity to cGMP-mediated vasodilatation and modulates the expression of genes in the p42/44 MAPK and p38 MAPK signaling cascades. This study tests whether angiotensin receptor blockade (ARB) with losartan decreases p42/44 MAPK or p38 MAPK signaling and preserves LZ+ MYPT1 expression in a rat infarct model of heart failure. In aortic smooth muscle, p42/44 MAPK activation increases and LZ+ MYPT1 expression falls after LAD ligation. Losartan treatment decreases the activation of p42/44 MAPK to the uninfarcted control level and preserves normal LZ+ MYPT1 expression. The expression and activation of p38 MAPK, however, is low and does not change following LAD ligation or with losartan therapy. These data suggest that either reducing or blocking the effects of circulating angiotensin II, both decreases the activation of the p42/44 MAPK signaling cascade and preserves LZ+ MYPT1 expression. Thus, the ability of ACE-inhibitors and ARBs to modulate the vascular phenotype, to preserve normal flow mediated vasodilatation may explain the beneficial effects of these drugs compared to other forms of afterload reduction in the treatment of heart failure
New insights into myosin phosphorylation during cyclic nucleotide-mediated smooth muscle relaxation
Sarcoplasmic Reticulum, Mitochondria and Filament Organization in Vascular Smooth Muscle
Elemental distribution in striated muscle and the effects of hypertonicity: Electron probe analysis of cryo sections
The involvement of Fyn tyrosine kinase and membrane rafts in the signal transduction in Ca2+-sensitization of vascular smooth muscle contraction
Electron probe analysis of sodium and other elements in hypertrophied and sodium-loaded smooth muscle.
Agonist-dependent modulation of Ca2+ sensitivity in rabbit pulmonary artery smooth muscle
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