It is suggested that the RhoA/ROK pathway is constitutively active in a number of organs under physiological conditions; its aberrations play major roles in several disease states, particularly impacting on Ca2+ sensitization of smooth muscle in hypertension and possibly asthma and on cancer neoangiogenesis and cancer progression.Expand
Abnormalities of these regulatory mechanisms and isoform variations may contribute to diseases of smooth muscle, and the G-protein-coupled inhibition of protein phosphatase is also likely to be impor-tant in regulating non-muscle cell functions mediated by cytoplasmic myosin II.Expand
Ca2+ sensitization by the Rho/Rho‐kinase pathway contributes to the tonic phase of agonist‐induced contraction in smooth muscle, and abnormally increased activation of myosin II by this mechanism is thought to play a role in diseases such as high blood pressure and cancer cell metastasis.Expand
The results of these studies indicate that in SMC, RhoA-dependent regulation of the actin cytoskeleton selectively regulates SMC differentiation marker gene expression by modulating SRF-dependent transcription and suggest that RHoA signaling may serve as a convergence point for the multiple signaling pathways that regulate SMC differentiate.Expand
The unchanged distribution of a permeant anion, chloride, argues against the existence of a large and sustained transSR potential during tetanus, if the chloride permeability of the in situ SR is as high as suggested by measurements on fractionated SR.Expand
It is concluded that AA induces Ca2+‐sensitization through dual mechanisms, one mediated by Rho‐kinase (or a related kinase), and (ii) Rho'kinase is not required for phorbol ester‐induced Ca2‐s Sensitization.Expand
The presence of both thick and thin myofilaments and of rough SR in smooth muscles supports the dual, contractile and morphogenetic, function of smooth muscle.Expand
Intermediate high voltage stereo electron microscopy of rabbit portal-anterior mesenteric vein smooth muscle showed that thick filaments are 2·2 μm long and have tapered ends, which could contribute to the ability of smooth muscle to develop equal or greater tension than striated muscle.Expand
The results suggest that the HMMosphatases of smooth muscle have properties common to type 1 protein phosphatases, but are inhibited only partially by high concentrations of inhibitor-2, and that the lower HMM phosphatase activity of tonic smooth muscle may contribute to its greater sensitivity toosphatase inhibitors and its slower rate of relaxation.Expand
It is concluded that AA may act as a messenger-promoting protein phosphorylation through direct inhibition of the form of protein phosphatase(s) that dephosphorylate MLC20 in vivo.Expand