[The influence of chronic neurotization on the monoaminergic systems of various brain structures in rats with various typological characteristics]

Abstract

Typological behavioral features of Wistar rats were tested in the open field and in Porsolt test. Rats were assigned to groups with high (HAct), medium (MAct), and low (LAct) behavioral activities. The same rats were assigned to high (HDep), medium (MDep) and low depressive (LDep) groups. The release of norepinephrine, dopamine, serotonin and their metabolites in homogenates obtained from the hypothalamus, hippocampus, frontal cortex and amygdala was assessed by microdialysis and HPLC. In these groups, the monoamine concentrations were different: the level of serotonin was higher in the hypothalamus and norepinephrine and 5-HIAA levels were lower in the hippocampus of MAct - MDep rats as compared to LAct - HDep. Chronic neurotization caused changes in monoamine concentrations in the hypothalamus and amygdala in rats of all groups, whereas in the hippocampus and frontal cortex monoamine changes were observed in HAct - LDep and LAct -HDep rats. The most prominent changes in monoamines levels in neurotized rats with different types of behavior were found in the frontal cortex, amygdala and hippocampus. The results show a correlation between the typological of behavioral characteristics and the reaction to stress of monoaminergic systems of the hypothalamus, hippocampus, frontal cortex and amygdala.