[31P NMR in vivo study of a rat brain with phosphate metabolism disorders after bilateral focal compression ischemia].

The dynamics of rat brain energy phosphates and intracellular pH was studied during the 1st hour after bilateral focal compression ischemia. The increased inorganic phosphate signal intensity was observed simultaneously with the unchanged pH and phosphocreatine level. Brain energy status was evaluated by the ATP level and by the Z-index (the averaged coefficients of correlation between NMR measured brain phosphates in a given group of animals). Reversible changes of both ATP and Z were observed after 16-28 min of recovery (20% of decrease and 200% of increase, respectively). Contrary to ATP the Z-value showed a significant increase in comparison with a corresponding intact value and with control (sham-operated animals). The Z-index is proposed as a sensitive criteria of brain energy status.