L-Palmitoylcarnitine-d9 is deuterium labeled L-Palmitoylcarnitine. L-Palmitoylcarnitine, a long-chain acylcarnitine and a fatty acid metabolite, accumulates in the sarcolemma and deranges the membrane lipid environment during ischaemia. L-Palmitoylcarnitine inhibits KATP channel activity, without affecting the single channel conductance, through interaction with Kir6.2[1][1][2].