[Effect of ischemia on the ultrastructure of the hypothalamo-hypophyseal system in rats].

The aim of this work was to elucidate the postischemic changes appearing in hypothalamic secretory nuclei (n. supraopticus and n. paraventricularis) and neurohypophysis in rats which underwent the incident of clinical death. The ultrastructural organization of secretory neurons and their axons in the neurohypophysis was investigated two weeks and one month after the insult. SO and PV neurons showed an increased number of polymorphic lysosomes, lipid droplets as well as an abundance of cytoskeleton elements, i.e., neurotubules and neurofilaments. Some astrocytic processes in the neuropil were swollen. Synaptic endings on SO and PV neurons had a normal ultrastructure. An increased number of lysosomes and dense bodies was observed in some axons and pituicytes in the neurohypophysis.