Background:

KN-93 hydrochloride is a potent inhibitor of Ca2+/calmodulin-dependent protein kinase II (CaMK II) with Ki value of 0.37μM [1].

KN-93 is an inhibitor of CaMK II. It exerts its effect by competing for the calmodulin binding site of CaMK II with IC50 value of 370nM. In isolated gastric parietal cells, KN-93 shows a potent inhibition of acid secretion induced by carbachol and histamine with IC50 values of 0.15μM and 0.3μM, respectively. It also inhibits forskolin induced aminopyrine uptake with IC50 value of 0.6μM. KN-93 is also found to have effects on the H+, K+-ATPase. 10μM KN-93 and 20μM KN-93 can inhibit 26% and 35% activity of the enzyme, respectively. Moreover, KN-93 is reported to act as an extracellular blocker of Kv channels through enhancing C-type inactivation [1, 2].

参考文献:
[1] Mamiya N, Goldenring J R, Tsunoda Y, et al. Inhibition of Acid Secretion in Gastric Parietal Cells by the Ca2+/Calmodulin-Dependent Protein Kinase II Inhibitor KN-93. Biochemical and biophysical research communications, 1993, 195(2): 608-615.
[2] Rezazadeh S, Claydon T W, Fedida D. KN-93 (2-[N-(2-hydroxyethyl)]-N-(4-methoxybenzenesulfonyl)] amino-N-(4-chlorocinnamyl)-N-methylbenzylamine), a calcium/calmodulin-dependent protein kinase II inhibitor, is a direct extracellular blocker of voltage-gated potassium channels. Journal of Pharmacology and Experimental Therapeutics, 2006, 317(1): 292-299.