INCREASE IN RENAL AND URINARY LOW AND HIGH-MOLECULAR-WEIGHT KININOGENS DURING CHROMATE-INDUCED ACUTE-RENAL-FAILURE IN THE RAT - EVIDENCE FOR RENAL KININOGEN PRODUCTION

In the present study, we investigated the plasma, urinary and intraren al concentrations of low and high molecular weight kininogens during s odium chromate (25 mg/kg body weight)-induced acute renal failure (ARF ) in the rat. Urinary kininogen underwent a transient increase with a maximum on day 7 (78 +/- 22 versus 4.2 +/- 1.6 ng bradykinin/mg creati nine) whereas plasma kininogen did not and glomerular filtration rate decreased (92 +/- 8 versus 895 +/- 70 mul/min). The tissue level of ki ninogen was enhanced both in the cortex (1,319 +/- 123 versus 86 +/- 8 pg bradykinin Eq/mg protein) and in the medulla (1,673 +/- 138 versus 44 +/- 9 pg bradykinin Eq/mg protein) but more in the medulla (36 +/- 4- versus 15 +/- 3-fold). As plasma kininogen level was unchanged and glomerular filtration rate decreased, the increase in both renal conc entration and urinary excretion of kininogen probably reflects stimula ted renal production of kininogen in this model of ARF. Whether the ev oked renal production of kininogen results from a local inflammatory r esponse only or may subserve another physiological purpose remains to be elucidated.