Increase in the adenine nucleotide translocase content of duckling subsarcolemmal mitochondria during cold acclimation

Intermyofibrillar and subsarcolemmal mitochondria were isolated from duckli ng gastrocnemius muscle. The adenine nucleotide translocase (ANT) content o f subsarcolemmal mitochondria was found to be half of that present in inter myofibrillar mitochondria, In addition, cold acclimation resulted in a 1.7- fold increase in subsarcolemmal mitochondrial ANT content, with intermyofib rillar mitochondrial ANT remaining constant. This change in mitochondrial A NT content correlates with the previously reported cold-induced change in t he sensitivity of mitochondria to palmitate-inhibited ATP synthesis [Rousse l et al, (1998) FEES Lett, 439, 258-262]. It is suggested that the mitochon drial ANT content enhances or reduces the fatty acid uncoupling activity in tissue, depending on the energetic state of mitochondria. (C) 2000 Federat ion of European Biochemical Societies. Published by Elsevier Science B.V. A ll rights reserved.