Concentration of Trypsin Inhibitors of Different Molecular Size and of Albumin and Haptoglobin in Blood and in Lymph of Various Organs in the Dog

The concentration and homogeneity of some plasma proteins in lymph from various tissues in dog was studied immunochemically. Special interest was focused on the enzyme inhibitors, at‐antitrypsin, and α2–macroglobulin. The ratio between the concentrations in lymph and plasma was the same for albumin and α1 antitrypsin, but decreased significantly with increasing molecular size in the order α1–antitrypin, haptoglobin and α2–macroglobulin. The ratio α1–antitrypsin/α2–macroglobulin was, on the average, twice as high in the intercellular fluid as in plasma. The protein content of the lymph varied considerably between the organs with the highest values for lung and liver. These organs also showed the lowest selectivity, expressed as the quotient between the α1–antitrypsin lymph/plasma ratio and the az‐macroglobulin lymph/ plasma ratio. The influence of different rates of lymph flow in different organs on these values is discussed. No enzyme‐inhibitor complexes were demonstrated.