Hyper-alpha-2-macroglobulinemia in narcotic addicts.
Significant increases of serum alpha-2-macroglobulin (alpha-2-M) were detected in narcotic addicts presenting at a methadone treatment center. The mean alpha-2-M level was 341 +/- 14 mg/dl compared with 231 +/- 8 mg/dl in normal persons (p less than 0.01). In a comparable group of alcoholics with laboratory evidence of hepatic dysfunction the mean alpha-2-M level was 208 +/- 10 mg/dl. Although the serum immunoglobulin M content was also substantially elevated in the narcotic-addict group, no correlation was obtained between the serum content of this protein and alpha-2-M. Similarly, no correlation between alpha-2-M level and serum zinc content was observed. When the values of the trypsin-binding activity of serum measured in 13 addicts, 15 alcoholics with laboratory evidence of hepatic dysfunction, and 16 normal subjects were plotted against the amount of alpha-2-M measured in the same subjects, a linear correlation was obtained between trypsin-binding activity and alpha-2-M. Thus, the significantly increased serum trypsin-binding activity observed in the addicts is that which might be expected if normal alpha-2-M is being accumulated in large amounts as a result of increased macroglobulin synthesis.