[The relationship of the nitric oxide level with angiotensin-converting enzyme activity in the chest injury].

We have studied NO production, ACE activity and their correlation in pleural fluid of patients with and without lung wound, in the blood serum of the wounded and blood donors. Chest wound was associated with a significant elevation of NO levels in all study groups versus controls. The greatest increase of ACE activity was observed in pleural fluid of patients with a lung wound. There was a negative correlation between NO and ACE in pleural fluid of patients with a lung wound. In all the other groups, a positive correlation between NO and ACE was revealed. ACE overactivity in the pleural fluid may be one of the factors of impaired relationship between NO and ACE in lung wound. Determination of ACE activity in the pleural fluid may serve as a diagnostic criterion of the lung injury.