IDENTIFICATION OF RAT URINARY KININ AS BRADYKININ

Bradykinin (BK)-like activity, which was detected by BK-enzyme-immunoa ssay, was purified from 80 ml of ureter urine of Sprague-Dawley rats b y Sephadex G 25 chromatography, FPLC, and reversed phase HPLC. The pur ified kinin fraction showed the same retention time as authentic BK on HPLC and produced contraction of isolated rat uterus, the contraction being suppressed by a B2-antagonist Hoe140. There was no other kinin detected on the HPLC at the corresponding retention time to kallidin, arginyl-BK or T-kinin. The peptide showed an amino acid sequence ident ical to that of BK by amino acid sequence analysis.