Abstract: | The ultrastructure of capillary walls of the mamillary bodies was studied in rats distributed in two age groups: adult (6-8-month-old) and old (28-30-month-old) animals under hypoxic hypoxia. It was found that age-related differences in the response of brain capillary walls to the injuring agent were reduced to a rapid increase in dystrophic phenomena and less conspicuous compensatory processes seen in the old animals. More profound injuries to other brain tissues adjacent to the vessels were also indicative of less efficacy of the adaptive reactions in the old animals. |