The role of nitric oxide synthase in the modulation of the immune response in atopic disease

Abstract

Present study aimed to determine the effect of endothelial and inducible nitric oxide synthase on the inflammatory process of soft tissues in the oral cavity of experimental animals in the modulation of atopic disease. To simulate the atopic process, young experimental animals (threemonth- old male rabbits) were sensitized by intraperitoneal injection of ovalbumin and aluminum hydroxide during the first 3 days of the experiment. Twice lower dose of ovalbumin was instilled intranasally under local anesthesia five days later (Day 8) with repeated intranasal administration of ovalbumin on the 16th, 17th, 20th and 21st day of the experiment. Obtained specimens of oral cavity were examined histologically, and immunohistochemical study was performed to determine the immunoreactivity of eNOs, iNOs, CD23, CD20. Histological investigation of obtained microslides detected that atopic modeling process is implemented by a complex of pathological changes of oral mucosa with the presence of intraepithelial lymphocytes, eosinophils, focal erosive lesions, signs of proliferation of the basal cell layer, moderately expressed papillomatosis. Such histological picture can be interpreted as the development of inflammatory, degenerative, dyscirculatory process. It was found that such changes are accompanied by disturbance of nitric oxide synthase metabolism, characterized by increased activity of inducible nitric oxide synthase more than twice and endothelial synthase in the extravascular space. Inflammatory infiltrate in atopic process is presented by B-lymphocytes, activated macrophages, eosinophils both in the lamina propria and epithelium that is indicated by a sharp increase in the immunoreactivity of CD23 and CD20. Accumulation of these cells has strong correlation dependence with nitric oxide synthase. The most pronounced correlation has been detected between CD23 and CD20 (r=0.89), iNOs and CD23 (r=0.85), iNOs and CD20 (r=0.87) while comparing the results of immunohistochemical study with eNOs, iNOs, CD23, CD20. The obtained data can be used as a basis for the development of preventive measures in patients with atopic diseases, based on the correction of disturbed nitric oxide metabolism.