Objective: To study the changes in plasma substance P (SP) and calcitonin gene-related peptide (CGRP) levels in children with acute asthma before and after gamma-aminobutyric acid (GABA) treatment.
Methods: Seventy-five children with asthma were randomly assigned to GABA treatment (n=36) and control groups (n=39). Both groups were given conventional treatment for asthma. Besides the conventional treatment, the treatment group was administered with oral GABA (25-30 mg/kg•d). Plasma content of SP and CGRP was measured using ELISA before treatment and after remission.
Results: There were no significant differences in plasma content of SP and CGRP between the GABA treatment and control groups (P>0.05) before treatment. Plasma content of SP and CGRP in the GABA treatment group was significantly lower than the control group (SP: 57±15 pg/mL vs 127±12 pg/mL; CGRP: 23±10 pg/mL vs 42±8 pg/mL) after remission (P<0.01). Plasma content of SP and CGRP after remission was significantly lower than before treatment (P<0.01) in both groups. There was a significantly positive correlation between plasma SP and CGRP content in asthmatic children (r=0.792, P<0.01).
Conclusions: GABA can significantly decrease plasma levels of SP and CGRP in children suffering from acute asthma.