Abstract
We previously reported that the atrial natriuretic polypeptide (ANP) caused a relaxant effect with the tissue cyclic GMP (c-GMP) levels on a guinea pig tracheal smooth muscle.
We studied plasma immunoreactive ANP and c-GMP concentrations in various situations in patients with respiratory diseases which were divided into 3 groups, patients with bronchial asthma (BA, n=16), patients with chronic pulmonary emphysema (CPE, n=10) and patients with pulmonary insufficiency induced by pulmonary tuberculosis (Tbc, n=44). One hundred and thirteen healthy subjects were also studied as a control group. This is the first report that these clinical markers have been measured at same time in the field of respiratory diseases.
In conclusion, 1) Plasma ANP was significantly higher in patients with BA (attack) (P<0.05) and Tbc (P<0.01) than in control. 2) Plasma c-GMP was significantly higher in patients with Tbc (P<0.01) than with BA (remission). 3) There was a significant correlation between plasma c-GMP and log ANP in patients with chronic respiratory disease (r=0.714, P<0.05, n=72). 4) Plasma ANP was significantly higher at attack than at remission (P<0.05).
These results indicate that effects of ANP in patients with respiratory disease may be, at least in part, mediated by c-GMP being in the place of cyclic AMP, and ANP induced by pulmonary hypertention may cause a relaxant effect on tracheal and vascular smooth muscle. Therefore, exogenous ANP may also be useful on the therapy of patients with bronchial asthma. such as intractable asthma.
