An arterio-venous study of serum alpha1-antitrypsin in patients with chronic bronchitis.

The effect of passage through the lung on alpha1-antitrypsin was studied in sixteen patients with chronic obstructive airways disease. The average mixed venous value of alpha1-antitrypsin (106.2% standard serum value) was not different from the the mean arterial value (105.6%). Where individual differences were found there was a similar difference in serum albumin. However, there was a small but significant rise (p less than 0.005) in serum alpha1-antitrypsin "complex" as blood traversed the lung (mixed value = 6.3%; mixed arterial value = 6.8%). The reason is not yet clear.