The Effect Of Cigarette Smoking On Content Of Calcitonin Gene-related Peptides In Airway Of Asthmatic Rats

Objective To investigate the change of calcitonin gene-related peptides (CGRP) content in airway of asthmatic rats, and the influence on the content from cigarette smoking, explore the effect of CGRP on asthma's pathogenesis and the influence on their roles from cigarette smoking.Methods Thirty two male Wistar rats were randomly divided into control group, smoke exposure group, asthma group and asthma combined smoke exposure group, n=8. Immunohistochemistry and computer image analysis were used to determine semi-quantitatively the content of CGRP protein in airway of rats.Result (1) Compared with control group (0.325±0.042), the CGRP content in airway of rats were remarkablely elevated in smoke exposure group (0.406±0.062), asthma group (0.458±0.055) and asthma combined smoke exposure group (0.502±0.072).The P values were all less than 0.01. (2) Compared with asthma group, the CGRP content in airway of rats were increased in asthma combined smoke exposure group. The P values was less than 0.05.Conclusion The elevated content of CGRP in airway of asthmatic rats indicates that CGRP may be involved in neurogenic inflammation in asthma's pathogenesis; smoke exposure can increase the content of CGRP in airway of rats, even the asthmatic rats, and aggravate the airway inflammation in the asthmatic rats, which may be one of the mechanisms in smoking-induced asthma attack or exacerbation.