[Novel mechanisms for increasing Ca2+ sensitivity of contractile apparatus in smooth muscle].
Smooth muscle contraction is primarily regulated not only by changes in cytosolic Ca2+ concentrations ([Ca2+]i) but also by changes in the force/[Ca2+]i ratio. The use of membrane-permeabilization technique facilitated demonstration of an increase in the level of force at constant [Ca2+]i (Ca2+ sensitization). It was clarified that Rho-associated kinase (Rho-kinase) is a novel mediator of Ca2+ sensitization of the smooth muscle contraction, by introducing the recombinant catalytic domain of Rho-kinase into the cytosol of vascular smooth muscle permeabilized with beta-escin. This review article focuses on novel mechanisms, by which activation of receptor-coupled G-protein(s) increases Ca2+ sensitivity of the contractile apparatus in smooth muscle: Rho-kinase and protein kinase C.
Todoroki-Ikeda
N
N
First Department of Physiology, Yamaguchi University School of Medicine, Ube.
Mogami
K
K
Ohmura
M
M
Yoshimoto
Y
Y
Matsuzaki
M
M
Oka
M
M
Kobayashi
S
S
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D003285:Contractile Proteins / Q000502:physiology*; D003600:Cytosol / Q000378:metabolism; D004928:Escin / Q000502:physiology; D047908:Intracellular Signaling Peptides and Proteins; D009119:Muscle Contraction; D009131:Muscle, Smooth, Vascular / Q000378:metabolism* / Q000502:physiology; D011493:Protein Kinase C / Q000502:physiology; D017346:Protein Serine-Threonine Kinases / Q000502:physiology*; D011994:Recombinant Proteins; D054460:rho-Associated Kinases
D003285:Contractile Proteins; D047908:Intracellular Signaling Peptides and Proteins; D011994:Recombinant Proteins; D004928:Escin; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D011493:Protein Kinase C; D002118:Calcium