Fig. 6.

Tandem pore domain acid-sensitive K⁺ channel 1 (TASK-1) effect on cardiac energetics and fatty acid oxidation. Average cardiac efficiency (A), average potential energy (B), and average pressure-volume area (C) were calculated from pressure-volume loops obtained on wild-type, TASK-1 global knockout (KO), and TASK-3 KO mice after 12 wk of either Sham or transverse aortic constriction (TAC) procedure. Error bars reflect means ± SE; n = no. of mice. Statistical comparisons were made using two-way repeated measures ANOVA. Statistically significant P values for the interaction between genotype and treatment conditions are shown. Comparisons between genotypes at each time point were made using Bonferroni’s test for multiple comparisons, *P < 0.05 vs. Sham state, †P < 0.05 vs. wild-type TAC, and ‡P < 0.05 vs. TASK-3 KO TAC. Heat map (D) showing C16 and C18 long-chain acylcarnitine in wild-type (WT) and TASK-1 KO mice after 7 days of either Sham or TAC procedure. Enhanced long-chain acylcarnitine expression is observed in the TASK-1 KO hearts after TAC. Scale bar indicates acylcarnitine concentration in μM. For this experiment, the following numbers of mice were used: n = 8 wild-type Sham, n = 8 wild-type TAC, n = 6 TASK-1 KO Sham, and n = 3 TASK-1 KO TAC.