A perspective of smooth muscle contractility through actions of vanadium compounds.
Smooth muscle contraction has a characteristic step-response with successive additions of stimulating compounds, and instant reversal on withdrawing the stimulus, indicative of an equilibrium situation wherein continuous, rapid reactions are occurring. Vanadium compounds, ortho- and meta-vanadates, decavanadate and peroxovanadate, were found to contract a variety of smooth muscles. Their actions were analyzed with respect to activation of receptors, increase in the intracellular calcium concentration, and increase in calmodulin-dependent myosin light chain phosphorylation leading to contraction. A new perspective of smooth muscle contractility has emerged from the studies with vanadium compounds suggesting control mechanisms involving phosphorylation for contraction and redox for relaxation.
Ramasarma
T
T
Department of Biochemistry, Indian Institute of Science, Bangalore.
Venkataraman
B V
BV
D000818:Animals; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects; D008564:Membrane Potentials / Q000187:drug effects; D009119:Muscle Contraction / Q000187:drug effects*; D009124:Muscle Proteins / Q000378:metabolism; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology*; D010084:Oxidation-Reduction; D010766:Phosphorylation; D011956:Receptors, Cell Surface / Q000187:drug effects; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors; D017968:Vanadium Compounds / Q000737:chemistry / Q000494:pharmacology*
D007473:Ion Channels; D009124:Muscle Proteins; D011956:Receptors, Cell Surface; D017968:Vanadium Compounds; D000254:Sodium-Potassium-Exchanging ATPase