[Morphofunctional characteristics of the spleen in rats with different behavior after exposure to restriction stress].

Spleen morphological characteristics were studied in rats with contrasting behavior towards man (aggressive and tame). It was shown that intact tame rats surpassed the aggressive ones in body mass, absolute and relative splenic mass and in diameter of lymphoid nodules. Humoral immune response to sheep erythrocytes in tame rats was significantly lower than in aggressive ones. Exposure to restriction stress for 4 hours stimulated formation of antibody-forming cells in the spleen and increased the differences in humoral immune response between the rats with contrasting behavior. In aggressive rats the exposure to stress caused significant increase in diameter of lymphoid nodules and their germinal centers, while in tame rats it resulted in augmentation of marginal zone thickness. The data obtained demonstrate for the first time the differences in morpho-functional characteristics of the spleen activity in response to restriction stress in animals with contrasting behavior.