The influence of post-mortem fixation delay on the reliability of the Golgi silver impregnation

Brains of guinea-pigs were studied using the rapid Golgi technique after formol fixation. The delay between death and fixation varied from 5 min to 24 h. A considerable drop in density of spines on the apical, basal and oblique dendrites of pyramidal V cells was found from 1.5 h onwards. The total length of the basal dendrite arborization showed a reduction after 4 h. It was concluded that, particularly for quantitative methods, a fixation delay of more than 4 h makes results progressively less reliable.