Sensory neuropeptides induce histamine release from bronchoalveolar lavage cells in both nonasthmatic coughers and cough variant asthmatics

Authors


Ennis Department of Clinical Biochemistry, Institute of Clinical Science, The Queen's University of Belfast, Grosvenor Road, Belfast BT12 6BJ, UK ( m.ennis@qub.ac.uk).

Abstract

Background

Sensory neuropeptides have been suggested to play a role in the pathogenesis of a number of respiratory diseases including asthma and chronic non-productive cough.

Objectives

To investigate the action of sensory neuropeptides on airway mast cells obtained by bronchoalveolar lavage (BAL).

Methods

BAL was performed on 23 nonasthmatic patients with cough (NAC), 11 patients with cough variant asthma (CVA) and 10 nonatopic controls. Washed lavage cells were stimulated (20 min, 37 °C) with calcitonin gene-related peptide (CGRP), neurokinin A (NKA) and substance P (25 and 50 μmol/L).

Results

The neuropeptides tested induced histamine release in all groups studied. Only CGRP (50 μmol/L) induced significantly more histamine release from both NAC and CVA patients compared with control subjects (= 0.038 and 0.045, respectively).

Conclusion

Regardless of aetiology, mast cells from patients with chronic cough appear to have an increased responsiveness to CGRP compared with controls. The results of the present study suggest that the role of CGRP in chronic cough should be further investigated.

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