[Ultrastructure of axosomatic contacts on sensomotor cortex neurons and celiac ganglia in rats in relation to age].

Axosomatic contacts of pyramidal neurons and those of neurones of celiac ganglia in rats are characterized by diverse types of relationships and by many-component complexes. The metric parameters of axosomatic contacts of pyramidal neurons do not change with age but the proportion of active contacts increases. With age, the celiac ganglia show an increase in the diameter of contact axons and in the number of deeply invaginated contacts. Meanwhile the proportion of active contacts diminishes. These changes within the system of axosomatic contacts appear to develop in response to subsidence of neurons and their contacts with age and thus have a compensatory-adaptive significance.