Nervolus Control of the Phagocytic System

Abstract

The complexity of the immune response, including numerous functional changes (thermoregulatory, circulatory, respiratory, metabolic etc.) led us (Benetato, Baciu & Wad, 1945) to hypothesize nervous hypothalamic control of this important homeostatic response. This work synthesizes the experimental results obtained in the last four decades by us on the nervous control of the phagocytic system. Unfortunately at that time those findings were uninteresting, immunity being satisfactorily explained as a purely cellular process. The phagocytic response of the mobile (neutrophils and monocyte) system to i.v. administration of bacteria, may be reproduced by direct electrical stimulation of the hypothalamic tuberomammillary area, and by electroshock. It is blocked after sectioning the spinal cord, or after barbiturates. Using the original isolated head technique, applied to dogs, it was demonstrated that the injection of Salmonella typhi murium suspension in the head circulation, may activate phagocytosis in the body, isolated humorally, only through nervous effector ways, which are conserved. The current explanation is that the bacteria in the common circulation of head activates macrophages, producing the endogenous pirogen factor (II l), which through area hypothalamica anterior acts on the tuberomammillary zone, triggering the phagocytic response by neural effector pathways. Phagocytosis stimulating substances appeared in blood, some as a result of activation of protease systems of the blood (coagulation, fibrinolysis, kininforming and complement). Epinephrine activates peripherally the fibrinolytic and kinin forming systems. Neuroimmunomodulatory effects were also demonstrated for the RES.

Key Words:

• phagocytic system
• phagocytic response
• hypothalamic modulation