OBJECTIVE: To study the changes of substance P (SP) content in plasma of asthmatic children and in the blood, bronchoalveolar lavage fluid (BALF) and lung tissues of asthmatic guinea pigs and SP mRNA expression, and to investigate the relationship between SP and asthma of children. METHODS: We determined the contents of plasma SP by the method of immunoassay at the stage of acute attack and clinical remission in 35 children with asthma. On the basis of asthma model of guinea pigs, we examined the contents of SP in the blood, BALF and lungs. The expression of SP mRNA in lungs was examined by RT PCR. RESULTS: ① At the stage of acute attack, the level of SP was higher than that of the stage of clinical remission and normal controls (P< 0.01 ). At the stage of clinical remission, the difference of SP contents was not obvious compared with that of controls (P> 0.05 ). ② The SP content of severe asthmatic children was higher than that of mild asthmatic children (P< 0.05 ). ③ In asthmatic guinea pig groups, SP contents in the blood, BALF and lungs were higher than those of normal ones (P< 0.01 ), and the expressions of SP mRNA in lungs were higher (P< 0.01 ). In repeatedly attack group, the SP content of guinea pigs was higher than that of asthma group (P< 0.05 ), and the expression of SP mRNA in lungs was also higher (P< 0.01 ).CONCLUSIONS: SP levels increased in asthmatic children and asthmatic guinea pigs, and the expression of SP mRNA was up regulated in the lungs of asthmatic guinea pigs. They were positive related to the severity of asthma. So SP has close relationship with asthma and may play a role in the mechanism of asthma."/>
Relationship Between Substance P and Asthma
Abstract OBJECTIVE: To study the changes of substance P (SP) content in plasma of asthmatic children and in the blood, bronchoalveolar lavage fluid (BALF) and lung tissues of asthmatic guinea pigs and SP mRNA expression, and to investigate the relationship between SP and asthma of children. METHODS: We determined the contents of plasma SP by the method of immunoassay at the stage of acute attack and clinical remission in 35 children with asthma. On the basis of asthma model of guinea pigs, we examined the contents of SP in the blood, BALF and lungs. The expression of SP mRNA in lungs was examined by RT PCR. RESULTS: ① At the stage of acute attack, the level of SP was higher than that of the stage of clinical remission and normal controls (P< 0.01 ). At the stage of clinical remission, the difference of SP contents was not obvious compared with that of controls (P> 0.05 ). ② The SP content of severe asthmatic children was higher than that of mild asthmatic children (P< 0.05 ). ③ In asthmatic guinea pig groups, SP contents in the blood, BALF and lungs were higher than those of normal ones (P< 0.01 ), and the expressions of SP mRNA in lungs were higher (P< 0.01 ). In repeatedly attack group, the SP content of guinea pigs was higher than that of asthma group (P< 0.05 ), and the expression of SP mRNA in lungs was also higher (P< 0.01 ).CONCLUSIONS: SP levels increased in asthmatic children and asthmatic guinea pigs, and the expression of SP mRNA was up regulated in the lungs of asthmatic guinea pigs. They were positive related to the severity of asthma. So SP has close relationship with asthma and may play a role in the mechanism of asthma.
