[Neural control of the respiratory nasal mucosa]

Re-evaluating the nasal cycle by long-term rhinoflowmetry: most individuals demonstrate a 'mixed' nasal cycle

BACKGROUND

The nasal cycle seems to be more complex than a strictly alternating swelling of the nasal mucosa. Long-term rhinoflowmetry (LRFM) allows continuous investigation of changes in nasal airflow over 24 hours (24h). We evaluated the various types of nasal cycle with LRFM over 24 hours and investigated the influence of age and gender.

METHODS

LRFM was continuously performed over 24h in 55 rhinologically healthy subjects (36 female, 19 male). The LRFM flow curves were examined for phases of the 'classical' 'in-concert' 'one-side' and'no-cycle' cycle types. Subjects were divided into 4 age subgroups (19-29; 30-49; 50-69; >70 years). Correlations of age and gender with the individual cycle forms were analyzed.

RESULTS

85.5% of the subjects presented a 'mixed' nasal cycle within 24h. 'classical' nasal cycle was seen most often (92.7% vs. 'in-concert' 56.4% vs. 'one-sided' 18.2% vs. 'no-cycle' 5.5%). Older age groups significantly more often presented the 'no-cycle' type. A tendency was seen towards a mixed nasal cycle with increasing age. The mixed nasal cycle was significantly more often seen in the female subjects.

CONCLUSIONS

LRFM is an easy-to-use measurement tool. The 'mixed' nasal cycle predominates. However, all 4 different cycle types can be detected, alternating over 24h in each subject. Moreover, the cycle type varies with age.

Inferior nasal turbinate mucosa shrinkage prior to surgery under local anaesthesia

INTRODUCTION AND OBJECTIVES

Chronic rhinitis-related complaints may result from isolated hypertrophy of the inferior nasal turbinates. If the symptoms persist despite conservative management, turbinoplasty is indicated. However, the nasal mucosa lining the inferior turbinates seems decongested immediately before the surgery performed under local anaesthesia, compared to the examination when the patients were entered for surgery. The study aimed to confirm this observation and to hypothesize as to the reasons for its occurrence.

PATIENTS AND METHODS

The measurements of the longest distances between the medial rim of the inferior nasal turbinate mucosa and nasal septum and the shortest distances between the lower rim of the turbinate and floor of the nasal cavity in the inferior part of both common nasal meatus, were carried out on photos taken during endoscopic examinations: the one entering the patient for turbinoplasty, and the other immediately before the procedure. The results in this group were compared to those obtained from patients operated on under general anaesthesia.

RESULTS

In 130 patients aged 18-60 (mean=40.7) years, operated on under local anaesthesia, the sum of the mean distances between the nasal septum and the medial rim of the lower turbinate in both nasal cavities, was 3.4mm during the first examination, and 4.5mm (p=.0008) during the second one. In the group of 42 participants aged 26-47, mean=36.8 years operated on under general anaesthesia, the values were: 4.8mm and 3.6mm (p=.02), respectively. The differences were significantly smaller in the smokers (.3) compared to non-smokers (1.3; p=.04) mm.

CONCLUSIONS

Records of the entering examination must be considered before turbinoplasty under local anaesthesia.

Rhinitis medicamentosa: Electron microscopic changes of human nasal mucosa

OBJECTIVE: Prolonged application of nasal vasoconstrictors causes rhinitis medicamentosa (RM). Nasal obstruction is induced by rebound swelling when the decongestive effect has disappeared. The aim of this study was to demonstrate ultrastructural changes in RM.

STUDY DESIGN AND SETTING: Tissue samples of inferior turbinates from 22 patients with RM and 10 patients without rhinitis were taken during nasal surgery. Ultrathin sections were investigated by using a transmission electron microscope (TEM).

RESULTS: The TEM findings revealed severe epithelial damages such as loss of ciliated cells. In the subepithelial region, the vascular endothelium showed gaps and ruptures of basal lamina.

CONCLUSION: RM is a drug-induced damage of human nasal mucosa. Loss and destruction of ciliated epithelial cells are the morphologic correlation of the disturbed mucociliary clearance. In addition, vascular endothelium revealed ultrastructural changes. This could be caused by an increased vascular permeability with consecutive interstitial edema.

SIGNIFICANCE: This study demonstrated new morphological aspects of rhinitis medicamentosa.

© 2007 American Academy of Otolaryngology–Head and Neck Surgery Foundation. All rights reserved.

The expression of adiponectin receptor is altered in mild and moderate/severe persistent allergic nasal mucosa

BACKGROUND

Adiponectin, one of the adipokines, has been implicated in the inflammatory process in patients with allergic rhinitis. The level of adiponectin is affected by immunotherapy. Considering the fact that adiponectin receptors (AdipoRs) mediate intracellular signaling events in response to the binding of adiponectin, the role of AdipoRs in healthy and allergic nasal mucosa should be determined. This study investigates the level of expression and distribution pattern of AdipoR1 and AdipoR2 in healthy, mild, and moderate/severe persistent allergic nasal mucosa to understand the role of adiponectin in allergic rhinitis.

METHODS

The level of expression and distribution pattern of AdipoR1 and AdipoR2 were evaluated in healthy, mild, and moderate/severe persistent allergic nasal mucosa, using semiquantitative reverse-transcriptase-polymerase chain reaction (RT-PCR), immunohistochemistry, and Western blot analysis.

RESULTS

AdipoR1 was expressed in healthy, mild, and moderate/severe persistent allergic nasal mucosa where it was commonly localized to the vascular endothelium. However, AdipoR2 was not expressed in any samples of nasal mucosa tested in the present study. Semiquantitative RT-PCR and Western blot analysis showed that the level of expression of AdipoR1 mRNA and protein was decreased in mild and moderate/severe persistent allergic nasal mucosa in comparison with healthy nasal mucosa, but not significantly different between mild and moderate/severe persistent allergic nasal mucosa.

CONCLUSION

These results indicate that AdipoR1 may play an important role in the pathogenesis of allergic nasal mucosa, suggesting a role for AdipoR1 in vascular dysfunction in mild and moderate/severe persistent allergic nasal mucosa.

[Immunocytochemical detection of caspase 3 in various diseases of human nasal mucosa]

BACKGROUND

Inflammatory processes play a central role in the pathogenesis of chronic rhinosinusitis (CRS), however, the impact of apoptosis in CRS in unclear. The aim of this study was a comparison of caspase 3 activity, a key enzyme in the apoptosis cascade, in samples of nasal tissue from patients with different types of rhinosinusitis.

MATERIAL AND METHODS

Immunohistochemical analyses were carried out to detect caspase 3 in samples of nasal tissue from patients with CRS and nasal polyps (NP), allergic rhinitis (AR), rhinitis medicamentosa (RM) and atrophic rhinitis.

RESULTS

Evidence of increased apoptosis was found in the epithelium, submucosal glands and blood vessels in NP samples. Samples of RM showed strong caspase 3 activity in the endothelial cells and the lamina muscularis of blood vessels. In atrophic rhinitis the epithelium and subepithelial glands showed increased caspase 3 activity. In samples of patients with allergic rhinitis caspase 3 activity could not be detected.

CONCLUSIONS

Activated apoptosis seems to play an important role in the pathogenesis of different types of rhinosinusitis. Further investigations on the induction of caspase 3 are necessary for the development of new therapeutic strategies to influence the regulation of apoptosis.

[Ultrastructural changes in allergic rhinitis vs. idiopathic rhinitis]

BACKGROUND

Nasal hyperreactivity is one of the most important underlying mechanisms in allergic rhinitis (AR) as well as idiopathic rhinitis (IR). The aim of the present study was to examine pathomorphological changes in nasal mucosa in these subgroups of rhinitis.

PATIENTS AND METHODS

Tissue samples of human inferior turbinates from 20 patients with AR and 16 patients with IR were taken during nasal surgery and preserved in glutaraldehyde or paraformaldehyde. Ultrathin sections of specimens from 15 patients without chronic inflammation of nasal mucosa were used as controls. Primary antibodies against substance P (SP), calcitonin-gene-related peptide (CGRP), and endothelial nitric oxide synthase (NOS III) were applied, and the immunocomplexes were visualized by an immunocytochemical staining technique using gold-labeled antibodies. Immunostained structures were photodocumented using light and transmission electron microscopy.

RESULTS

The nasal mucosa of patients with AR and IR showed similarities on the ultrastructural level. A strong innervation pattern with sensory nerve fibers containing SP and CGRP demonstrated neurogenic inflammation. Extensive edema and cellular infiltrations were found in AR. A decreased presence of eosinophils and nitric oxide was observed in IR.

CONCLUSIONS

On the ultrastructural level, AR and IR showed many similarities but also some differences. Based on these findings, anti-inflammatory therapy could be recommended for both types of rhinitis.

Over-expression of neuropeptide urocortin and its receptors in human allergic nasal mucosa

OBJECTIVES

Urocortin (UCN) is a member of the corticotropin releasing factor (CRF) neuropeptide family. UCN act as locally expressed proinflammatory factor and induce mast cell degranulation, cytokine secretion, and trigger vascular permeability, which are mediated by CRF receptors in peripheral tissues. Considering its functional roles, UCN and its receptors may play a role in the pathogenesis of allergic nasal mucosa. Therefore, we investigated the expression profile and distribution of UCN and CRF receptors in normal and allergic nasal mucosa.

METHODS

Reverse transcriptase-polymerase chain reaction, immunohistochemistry, and Western blotting were applied to the normal and allergic nasal mucosa.

RESULTS

The expression levels of UCN and CRF receptors were increased in allergic nasal mucosa in comparison with normal nasal mucosa. In normal nasal mucosa, UCN and CRF receptors were restricted to the vascular endothelium of submucosal cavernous sinusoids where faint staining was found. However, in allergic nasal mucosa, UCN was expressed in small vessels distributed in lamina propria and the vascular endothelium of cavernous sinusoid located in submucosa. Many scattered positive cells were also found in allergic nasal mucosa, probably UCN-positive leukocytes. CRF receptors were also localized in the vascular endothelium of small vessels and cavernous sinusoid.

CONCLUSIONS

These results indicate that UCN may play a role in the regulation of vascular swelling in normal nasal mucosa. Moreover, in allergic nasal mucosa, increased expression levels of UCN and its receptors may contribute to increased mucosal swelling and vascular permeability, playing an important role in the pathogenesis of allergic rhinitis.

Ultrastrukturelle Veränderungen der Nasenschleimhaut des Menschen nach Abusus von topischen α-Sympathomimetika

BACKGROUND

Long-term abuse of decongestive nasal drops causes rhinitis medicamentosa due to cytotoxic and ciliary-toxic effects. Nasal obstruction is caused by rebound swelling when the decongestive effect has disappeared. The patient starts using nasal drops more frequently as a result of tachyphylaxis.

PATIENTS AND METHODS

Tissue samples from human inferior turbinates from 22 patients who had overused decongestive nose drops were taken during nasal surgery and preserved in phosphate-buffered paraformaldehyde or glutaraldehyde. Ultrathin sections were cut. The samples were dehydrated and embedded in Araldit. The findings were photo-documented using a light- and transmission electron microscope. Biopsies from ten patients without chronic inflammation of the nasal mucosa were used as controls.

RESULTS

The electron microscopic investigations revealed epithelium showing severe damage corresponding to regions with hyperplastic and metaplastic changes. Loss of ciliated cells was observed. Under a thick basal membrane, ultrastructural changes to the endothelial lining, such as openings and rupture of the basal lamina, were detected. Prominent endothelial cells were conspicuous.

CONCLUSIONS

Rhinitis medicamentosa is a drug-induced injury to human nasal mucosa associated with the prolonged abuse of topical nasal decongestants. Loss and destruction of ciliated epithelial cells are the morphological correlation to the disturbance of mucociliary clearance. Endothelial cells of capillaries, in particular, revealed ultrastructural changes indicative of increased permeability with consecutive interstitial edema.