Inflammatory Response as Exhibited by the Granuloma Pouch of the Rat * by Patricia

Numerous field and clinical observations and the results of many experimental studies have shown that nutritional deficiencies and infections in both human beings and experimental animals may be interrelated (1-4), Often, there appears to be a heightened susceptibility to infection on the part of the host (5-10). No complete explanation for this is available. The present investigation was designed to determine what effect malnutrition, induced by feeding a protein-deficient diet, has on the inflammatory response as exhibited by the granuloma pouch of the rat (11), and to study the behavior of some of the adaptive mechanisms accompanying malnutrition and inflammation. Severe protein malnutrition has been shown to depress the reticuloendothelial lymphoid system (12), and to result in a decrease in the number and function of cells involved in antibody production and phagocytic activity (12-16). Also, nutritional deficiency may seriously impair the latter or the repair stage of the inflammatory response (17-20). However, little is known of the effect of malnutrition on the over-all process of inflammation. This was studied in the present experiments by means of the granuloma pouch technique of Selye (11) which was selected for use because: (a) Pouch formation places a limited amount of stress on the host (21). (b) The pouch provides a semi-independent body cavity of a reproducible size and structure (11). Unlike natural body cavities such as the peritoneal cavity, the injection of irritants into the pouch cavity does not directly affect other body organs, e.g., liver, kidney, and spleen.