[Stress-induced changes of hypothalamic structure cell responses to antigen injection (LPS) (revealed by c-Fos...

Stress stimuli are known to influence the intensity if immune response. To elucidate the role of central regulating structures in this changes, analysis of activation level of hypothalamic neurons (revealed by quantity of c-Fos-positive cells) was carried out in rats within 2 hours after intravenous LPS injection and after this--impact associated with electric pain stimulation (EPS). The investigation was carried out in 52 male Wistar rats, 200-250 g. The c-Fos protein expression was analyzed with immunohistochemical method. The increase of c-Fos-positive cells number in 2 hours after LPS injection was observed in AFTN, PVH, LHA, VMH, DMH and PH. After electrical pain stimulation, the quantity of c-Fos-positive cells increased in the same structures. Combined application of electric pain stimulation and LPS injection results in diminished activation level in AHN, PVH, LHA and VMH as compared with typical response to single LPS injection without EPS. The EPS suppresses intensity of the immune response induced by injection of LPS (revealed by local hemolysis method with calculation of antibody-forming cells quantity (%) in the rat spleen). Thus the activation level changes of hypothalamic structures (AHN, PVH, LHA, PH) correlate with development of stress-induced immunosuppression, i. e. morphofunctional description of hypothalamic structures activation as revealed by pattern of activated cell alterations in hypothalamic structures during realization of stress-induced changes of immune system responses to antigen injection.