Biochemical Studies of Mitochondria from Ischemic Rat Hearts.

摘要

The capacity of mitochondria to transport adenine nucleotides during a period of cardiac ischemia and during recovery from ischemia is being evaluated. Mitochondria from rat hearts made partially ischemic for 20and 60minutes had slightly diminished capacity to synthesize ATP. Transport of adenine nucleotides is not inhibited by high levels of palmityl CoA in the matrix when levels of ATP and ADP are normal. However,when ATP and ADP levels are low due to increases in matrix AMP levels some inhibition due to matrix palmityl CoA can be observed. When AMP levels in the matrix rise due to the presence of arsenite,an inhibitor of alpha-ketoglutarate dehydrogenase,or rotenone, a respiratory inhibitor,AMP can leak out of mitochondria lowering the matrix nucleotide pool. This depletion of the nucleotide pool results in an irreversible loss of the capacity of the mitochondria to synthesize ATP.