Rats were bled to a mean arterial pressure of 40 mm Hg until the onset of decompensatory shock (marked by the need to return some blood in order to maintain the blood pressure) at which time all the shed blood was returned. 31P-nuclear magnetic resonance (NMR) spectra of their livers were collected during the shock and a subsequent 60 min recovery period. Adenosine triphosphate (ATP) levels fell linearly with time, in some instances to zero during shock. ATP recovery was very rapid after return of shed blood but did not return to its preshock values. Levels of ATP remained stable during the 60 min of recovery. From the rapid recovery after total depletion of ATP in this study and in other NMR studies on perfused ischemic livers, as well as the discrepancy in residual levels of ATP during shock and ischemia as measured by in vivo NMR or by extraction techniques, we argue in favor of metabolically inaccessible pools of adenine nucleotides during these hepatic stresses.