Figure 7.
Inhibition of pmKATP channels abolished the protective effects of UA-8 in starved HL-1 cells and NCMs. HL-1 cells and NCMs were starved for 24 h in the presence of UA-8 (1 μM) with or without HMR-1098 (10 μM), a pharmacological inhibitor of pmKATP channels. Treatment with UA-8 reduced release of LDH from starved HL-1 cells (a) and NCMs (e), indicative of increased cell survivability. HMR-1098 abolished stimulating effect of UA-8 on contractility of both HL-1 cells (b) and NCMs (f) under normal conditions and after 24 h of starvation. Inhibition of pmKATP channels with HMR-1098 significantly abolished the ability of UA-8 to prevent activation of caspase-3 and proteasome activity in starved HL-1 cells (c, d) and NCMs (g, h). Values are represented as mean±S.E.M., N=3. Significance was P<0.05, *significantly different from control nonstarvation, #significantly different from UA-8 treatment or statistically not different (ND)