Immunoheterogeneity of serum calcitonin in heroin addicts

Serum calcitonin (CT) concentrations were determined in 96 heroin addicts. CT levels were assayed by radioimmunological method employing two antisera, one vs. the 17-32 fraction (IMN) of the human CT, the other vs. the 11-32 fraction (B7). In heroin addicts the CT mean values were significantly higher (P less than 0.001) than in normal subjects (141 +/- 16.0 and 292 +/- 21.7 pg/ml with IMN-antiserum and with B7-antiserum, respectively, in heroin addicts; 64 +/- 7.8 and 189 +/- 21.7 pg/ml in controls). Serum CT levels assayed with B7-antiserum were notably higher (P less than 0.001) both in controls and in heroin addicts. Our results draw attention to the heterogeneity of high ICT values found in heroin addicts.