Changes And Clinical Significance Of Plasma Nitric Oxide And CAMP/cGMP Ratio In Children With Asthma

Objective To observe clinical significance and the changes of plasma nitric oxide (NO) and cAMP/cGMP ratio in children with asthma. Methods Plasma nitric oxide(NO), cAMP and cGMP levels in 40 asthmatic children in acute attack stage (pre-therapy)and restoration stage (post-therapy) and in 23 health children were measured by nitric acid reductase method and radioimmunoassay. Results (l)Asthmatic children in acute attack stage had increased amounts of the plasma NO3-/NO2- compared with that in restoration stage and in normal control subjects (135.8±35.9umol/L vs83.5±30.1umol/L, P<0.01; 135.8±35.9umol/L vs 78.2±24.5umol/L, P<0.01). (2) Plasma cGMP levels of asthmatic children in acute attack stage were higher than that in restoration stage and in normal control subjects (6.44±2.18pmol/mL vs 5.07± 2.54pmol/mL, P<0.05; 6.44±2.18pmol/mL vs 4.82±1.88pmol/mL, P<0.01) . (3) Plasma cAMP levels in acute attack stage were lower than that in restoration stage and in normal subjects ( 14.30±3.72pmol/mL vs17.73± 3.62pmol/ml,P<0.01; 14.30±3.72pmol/mL vs 18.11±3.99pmol/ml, P<0.01). (4)The cAMP/cGMP ratio of asthmatic children in acute attack stage was lower than that in restoration stage and in normal subjects (2.31±0.48 vs5.01± 1.35 ,P<0.01; 2.31±0.48 vs 4.14±1.35,P<0.01) . (5) Plasma NO3-/NO2-, cAMP and cGMP levels and the cAMP/cGMP ratio in restoration stage had no changes compared with that in nonnal control subjects (P>0.05). (6)The results of linear correlation analysis showed that there were positive correlations between plasma NO3-/NO2- and plasma cGMP levels in acute attack stage (r=0.401 P<0.01). Conclusions These results indicated that plasma NO and cAMP, cGMP levels are associated with the pathogenesis of bronchical asthma in children. This study suggest that plasma NO3/NO2- levels and cAMP/cGMP ratio may be a helpful index for evaluating of severity and therapeutic effects in asthmatic children.