ABSTRACT
Neuropeptides are chemical mediators in the sensory parasympathetic and sympathetic neurons of the airways. Numerous neuropeptides are selectively and specifically released from the lung tissues e.g., neuropeptide Y [NPY], vasoactive intestinal peptide [VIP], calcitonin gene-related peptide [CGRP], substance P [SP] and tachykinins [TK]. The imbalance between these neuropeptides is considered as one of the underlying mechanisms of bronchial asthma as some of them are potent bronchodilators whereas others are potent bronchoconstrictors. NPY is one of the important neuropeptides involved in the regulation of mechanisms of bronchial asthma. The aim of this work is to study the role of NPY in acute exacerbation of bronchial asthma in children. The study included two groups: patient group consisting of 30 children selected on clinical basis being presented with acute exacerbation of bronchial asthma and 20 apparently healthy age and sex-matched children as controls. None of the patients used oral steroids. For all patients, two plasma samples were obtained before and after treatment with bronchodilators whereas one plasma sample was collected from each member of the control group. Plasma level of NPY was determined by quantitative enzyme immunoassay after an extraction step for the tested plasma by column extraction method to separate peptides from any interfering substance. There was a significant higher plasma levels of NPY for patients in comparison to controls [10.5 +/- 4.6ng/ml versus 0.13 +/- 0.05 ng/ml P < 0.001] whereas there was no significant difference between NPY plasma levels before and after treatment [10.5 +/- 4.6ng/ml versus 10.02 +/- 4.1ng/ml; P>0.05]. The increased plasma levels of NPY during exacerbation of bronchial asthma act as a breakdown mechanism against the exacerbation of this asthma so it can be useful as a diagnostic tool for asthma but can't be employed as a predictor for responsiveness to therapy like other neuropeptides as there was no significant difference between its levels before and after treatment. Further future studies are recommended for better underst and ing of the neural mechanisms of NPY and other neuropeptides in bronchial asthma which might provide. fruitful therapeutic approach