Characterization and function of MYPT2, a target subunit of myosin phosphatase in heart.

Characterization of cardiac MYPT2 (an isoform of the smooth muscle phosphatase [MP] target subunit, MYPT1) is described. Several features of MYPT2 and MYPT1 were similar, including: a specific interaction with the catalytic subunit of type 1 phosphatase, delta isoform (PP1cdelta); interaction of MYPT2 with the small heart-specific MP subunit; interaction of the C-terminal region of MYPT2 with the active form of RhoA; phosphorylation by Rho-kinase at an inhibitory site, Thr646 and thiophosphorylation at Thr646 inhibited activity of the MYPT2-PP1cdelta complex. MYPT2 activated PP1cdelta activity, using light chains from smooth and cardiac muscle, by reducing K(m) and increasing k(cat).

Rho/Rho-kinase pathway contributes to C-reactive protein-induced plasminogen activator inhibitor-1 expression in endothelial cells.

Objective: Rho/Rho-kinase pathway plays pivotal roles in cardiovascular diseases including arteriosclerosis and hypertension. Recently it has become evident that C-reactive protein (CRP), a powerful marker for cardiovascular events, has direct proatherothrombotic effects on vascular cells. However, its molecular mechanism has not been fully investigated.

A case of primary cardiac lymphoma located in the pericardial effusion.

Primary cardiac lymphoma is a rare disorder with a poor prognosis. We present here a case of 77-year-old woman who was diagnosed as having cardiac lymphoma antemortem according to a cytologic examination of the pericardial effusion. Determination of the levels of serum-soluble interleukin-2 receptor and serum deoxythymidine kinase was useful for the diagnosis.

RhoA activation in vascular smooth muscle cells from stroke-prone spontaneously hypertensive rats.

RhoA is commonly activated in the aorta in various hypertensive models, indicating that RhoA seems to be a molecular switch in hypertension. The molecular mechanisms for RhoA activation in stroke-prone spontaneously hypertensive rats (SHRSP) were here investigated using cultured aortic smooth muscle cells (VSMC). The level of the active form of RhoA was higher in VSMC from SHRSP than in those from Wistar-Kyoto rats (WKY).