The protective effect of hypothermia on reversibility in the neuronal function of the hippocampal slice during long lasting anoxia.

The reversibility of neuronal function (postsynaptic potential and level of high energy phosphates) during deprivation of oxygen and/or glucose at 37, 28 and 21 degrees C was studied using hippocampal slices. The resistance of the neurons per se against anoxia could be well determined in the brain slice free from post-anoxic circulatory disturbance. During deprivation of oxygen and glucose the survival time, the period of deprivation of oxygen and glucose during which neurons of the tissue slice can survive for recovery, was at 10, 15 and 45 min at 37, 28 and 21 degrees C, respectively. During deprivation of glucose only it was 1.5, 3 and 5 h at 37, 28 and 21 degrees C. During deprivation of oxygen only the survival time was 2.5, 5 and 15 h at 37, 28 and 21 degrees C. Deep hypothermia (21 degrees C) and the presence of glucose prolonged tremendously the survival time of the neurons of tissue slice during long-lasting anoxia.