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EGF receptor kinase suppresses ciliogenesis through activation of USP8 deubiquitinase

Chemokines protect vascular smooth muscle cells from cell death induced by cyclic mechanical stretch.

New photic stimulating system with white light-emitting diodes to elicit electroretinograms from zebrafish larvae.

Potential protective function of the sterol regulatory element binding factor 1-fatty acid desaturase 12 axis in early-stage age-related macular degeneration

Activation of Sterol Regulatory Element Binding Factors by Fenofibrate and Gemfibrozil Stimulates Myelination in Zebrafish

tThe binding of the calcium channel blocker, bepridil, to calmodulin.


Itoh H, Tanaka T, Mitani Y, Hidaka H.
Biochem Pharmacol. 1986 Jan 15;35(2):217-20.


Bepridil had the highest relative potency for inhibition of myosin light chain kinase (MLCK) activated by Ca2+-calmodulin of all the calcium channel blockers we examined. Kinetic analysis indicated that the primary effect of bepridil was mediated through a competitive inhibition of the enzyme activation by interaction with calmodulin and the apparent Ki value of this agent was 2.2 microM. We then examined the binding of bepridil to calmodulin, using the equilibrium column binding technique. [3H]bepridil bound to the calcium-calmodulin complex, but not to calmodulin in the presence of 2 mM EGTA. Scatchard analysis of the binding of bepridil to calmodulin demonstrated that the dissociation constant was 6.2 microM and the calculated number of specific binding sites was about 5 sites per molecule of calmodulin. The concentrations of unlabeled bepridil, W-7, prenylamine, verapamil and diltiazem producing 50% inhibition (IC50) of the binding of [3H]bepridil to calmodulin were 4 microM, 28 microM, 45 microM, 130 microM and 700 microM, respectively. However, nifedipine and nicardipine did not displace [3H]labeled bepridil from calmodulin. There was a good correlation between the displacement of [3H]bepridil from calmodulin and the inhibitory effect on MLCK by these calcium channel blockers and W-7. These results suggest that bepridil binds to calmodulin in the presence of calcium and potently inhibits the phosphorylation of myosin light chain.