Ultrastructural changes in the hypothalamic secretory nuclei of rats depending on the duration of clinical death

The studies were carried out on neurosecretory nuclei of rat hypothalamus following complete circulatory arrest for 5 min (group I) and 10 min (group II). The surviving time of the animals after the experiment was 6 weeks. In group I, the ultrastructural appearance of the perikaryonic areas of the neurons indicates increased metabolic activity of these cells. Crinophagocytic bodies were noted near the Golgi apparatus. In the processes of neurons changes in the structure of the cytoskeletal elements were observed. In group II significant differences were noted, as compared with group I. They consisted in the desolation of the rough endoplasmic reticulum membranes from ribosomes, dilatation of the Golgi area cisternae, and swelling of mitochondria. In the perivascular region cells with the surface of the cytoplasmic processes membranes covered by the product of the Alcian blue reaction were noticed. In our opinion these cells may represent "cerebral macrophages". The ultrastructural changes were more pronounced in animals of group II, as compared with animals of group I.