Comparative studies of fresh and postmortem isolated rat cortical synaptosomes: morphology, K+ transport, and respiration.

Synaptosomal fractions were isolated from rat cerebral cortex immediately and at 1, 2, 3, and 4 h postmortem. The capability to undergo function-dependent configurational changes in relation to ouabain- and protoveratrine-sensitive K+ uptake, and the rate of O2 consumption were compared between fresh and postmortem synaptosomal fractions. Our results suggest that a 2 h postmortem storage at room temperature does not decrease substantially the functional performance of synaptosomes, while longer storage periods interfere with their capacity to maintain intracellular cation levels. The findings appear to be relevant to the use of human autopsy material for the preparation of synaptosomes.