[Postmortem changes of fine structure in the auditory pathways (organ of Corti and nucleus cochlearis of the guinea pig (author's transl)].

Autolytic changes in the guinea pig cochlear nucleus were studied by means of light- and transmission electron microscopy from 5 min. up to 5 h post mortem. Hyperchromasy and shrinking of neurons was observed already after 5 min. in areas, where the neurons have a high number of primary afferent nerve endings (Kane 1973). A second mode of post mortem degeneration was found. It was characterized by a swelling of the cell, which showed a diminished stain-ability. This lytic swelling seemed to be less rapid and probably less harmful in the beginning. The cochleae were examined by scanning electron microscopy. In contrary to known damaging agents (like noise or antibiotics) the outer haircells showed hardly any changes in the surface structures up to 1 hour in the basal coil, while lytic protrusions were observed in outer and inner haircells already after 5 min. in the apical parts. Post mortem changes in the cochlea and in the nucleus cochlearis show two different modes of autolytic degeneration.