[Reaction of the rat brain capillaries to immobilization stress]

Using calcium-adenosine triphosphate histoangiological method of Chilingarian, the morpho-functional state of the capillary limb of the microcirculatory bed in rat brain was studied at various time intervals after the exposure to experimental immobilization stress (fixation of the animals on the back for 2 hours). The analysis of morphometric data has show that in comparison with intact animals, immediately after the stress the capillaries were contracted by 17.2%, while on the second day their compensatory dilatation by 2.5% took place, which was later followed by a small contraction of 5.6%. Morphometric parameters of the placid and aggressive groups of animals indicate that the behavioral stereotype of placid animals secures more sparing physiological response to stress. It is suggested that the differences in capillary dysfunction significantly depend on the degree of lesions of the neuronal systems, which are involved in microcirculation control.