Synthesis of Adenosine Triphosphate by an Enzyme System from Ischæmic Muscle

Abstract

WHILE investigating the changes in phosphates of muscle in tourniquet shock, Bollman and Flock¹ have confirmed and amplified our previous finding (Green)² by showing that the adenosine triphosphate content of rat muscle falls progressively after clamping of the limb to reach a very low level at the time (four hours) at which, when both limbs are involved, fatal shock develops after release. They conclude that "this type of shock is definitely not due to ATP washed out of the muscle because ATP is destroyed during the occlusion and its decomposition products appear to be relatively non-toxic". In our opinion, the results of Bollman and Flock¹ only allow the conclusion that tourniquet shock is not due to a sudden release of adenosine triphosphate into the circulation on removal of the clamp. We never considered it likely that this was the mechanism, since a single dose of adenosine triphosphate injected intravenously produces acute symptoms and not the gradual merging into a shock-like state seen in ischæmic shock and after injection of adenosine triphosphate by routes other than the intravenous².