Influence of vagotomy on pulmonary calcitonin gene-related peptide in rats

Objective To investigate the influence of vagotomy on the expression of pulmonary calcitonin gene-related peptide (CGRP) in rats. Methods 30 male Sprague-Dawley rats were randomly divided into 3 groups according to the time after receiving left side vagotomy:1 week group (n=10), 1 month group (n=10), and 3 months group (n=10), another 10 normal rats as control group. Serum concentration of CGRP was detected by radioimmunity analysis, and RT-PCR method was used to measure the expression of CGRP mRNA in lung. Results Serum levels of CGRP were decreased, while pulmonary levels of CGRP mRNA were increased, in 1 week group and 1 month group than those in control group (P0.01), but there were no significant differences between 3 month group and control group (P0.05). Conclusion Serum level of CGRP is decreased, and pulmonary level of CGRP mRNA is increased in rats after vagotomy, which indicates that the vagus can regulate the expression of CGRP.