Clinical significance of nitric oxide synthase mRNA expression in patients with congenital heart disease associated with pulmonary hypertension

AIM: To explore the pathophysiological significance of nitric oxide(NO) and nitric oxide synthase(NOS) in congenital heart defects with pulmonary hypertension. METHODS: Twenty-four patients with congenital heart defects were divided into 3 groups: mild pulmonary hypertension group(n=8), moderate or severe pulmonary hypertension group(n=9), and non-pulmonary hypertension group(n=7). NOS mRNA expression was detected in lung tissues with reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: The NOS mRNA expression levels in the patients with moderate or severe pulmonary hypertension were much lower than those in the ones with mild-pulmonary hypertension or non-pulmonary hypertension (P 0.05). There was an inverse correlation between the NOS mRNA expression level and the pulmonary arteriopathy in the patients with pulmonary hypertension (r=-0.833, P0.01). CONCLUSION: In patients with congenital heart defects associated with pulmonary hypertension, NO and NOS play a role in pathological process of pulmonary arteriopathy, and the NOS mRNA expression level was proportional to the severity of pulmonary hypertension or pulmonary arteriopathy.