Objectives Description of the ultrastructural localization of nitric oxide synthase in the blood vessels of the nasal respiratory mucosa in patients with vasomotor rhinitis.
Study Design This research was conducted on seven patients—men and women, ages 20 to 45 years—suffering from vasomotor rhinitis and who had undergone surgical therapy for reduction of the inferior turbinates.
Methods To study the ultrastructural localization of nitric oxide synthase, NADPH-diaphorase cytochemistry was employed. Samples of the nasal mucosa were obtained from inferior turbinates.
Results The endothelial cells of the arterioles, capillaries , venules and cavernous sinuses revealed a distribution of the enzymatic activity similar to that found in unaffected subjects. A strong enzymatic activity was recognized in the smooth muscle cells of the cavernous sinuses. The smooth muscle cells of arterioles and venules were generally found to be negative to enzymatic reaction.
Conclusions This study suggests that the vascular disorders of the vasomotor rhinitis depend, at least in part, from nitric oxide synthase induction in the smooth muscle cells of the cavernous sinuses.