Expression of Inducible Nitric Oxide Synthase in Rat and Guinea PigRespiratory Epithelium after Capsaicin Treatment / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Nitric oxide (NO) production in the respiratory epithelium and the demonstration of inducible nitric oxide synthase in ciliated epithelium of the upper airway have recently been reported. The aim of this study was to investigate the expression of inducible nitric oxide synthase in the nasal epithelium after capsaicin treatment, which stimulates the substance P innervation. MATERIALS AND METHODS: In vivo treatment -Capsaicin (112 nM) was applied to the nasal cavities of the rat and guinea pig, and 30 nl of normal saline was applied for the control groups. After 2 hours, animals were sacrificed with cardiac perfusion of 4% paraformaldehyde and septal mucosa were removed. The 8 nm serial frozen tissue sections were made, and the expression of inducible nitric oxide synthase was determined using nicotinamide adenine diphosphate-diaphorase histochemistry. In vitro treatment- The nasal septum of the rats and the trachea of the guinea pigs were incubated in DMEM culture media with or without 112 nM capsaicin for experimental or control groups. After 0, 30 or 120 minutes of incubation, the tissues were fixed and processed for nicotinamide adenine diphosphate-diaphorase histochemistry. RESULTS: Both in vivo and in vitro studies demonstrated that the strong positive histochemical reactivity were observed in the respiratory epithelium of the rats and guinea pigs after capsaicin treatment compared to control groups. CONCLUSION: These data imply that capsaicin induces the expression of inducible nitric oxide synthase and that the substance P innervation of the nasal mucosa may have a protective role in the airway defense mechanism through nitric oxide production.

Allergic Fungal Sinusitis: A Report of Two Cases

Allergic fungal sinusitis (AFS) is a benign, noninvasive form of fungal sinusitis. Histologically, AFS is characterized by allergic mucin, which consists of eosinophilic mucinous material with occasional laminar deposits of eosinophils. A diagnosis of AFS can be made when there is a demonstration of characteristic allergic mucin and an appearance of fungal hypae scattered within the mucin with no evidence of tissue invasion, or when fungi cultures yield positive results. Until now, no cases of AFS have been reported in Korea, though there have been many cases of mycetomas and a few cases of invasive fungal sinusitis. We present the first two cases of AFS in Korea. The patients demonstrated characteristic allergic mucin, fungal hypae scattered within the mucin, and no evidence of tissue invasion on histopathology. Nasal polyps, involvement of the unilateral sinuses, peripheral eosinophilia, an elevated total IgE, and hyperattenuated masses observed in the CT supported the diagnosis of AFS. The patients recovered and did not display recurrence after surgery and treatment with topical steroids and saline irrigation.