[Urinary kallikrein and risk of lead poisoning].

Urinary kallikrein is an enzyme, probably originated in the kidney, which acts on plasma kininogen to produce kallidin, the decapeptide precursor of bradykinin, and appears to be implicated in various forms of arterial hypertension. It is significantly decreased in workers exposed to lead showing no hypertension or other clinical signs of lead poisoning. In respect to measurement of ALA or other heme precursors the determination of urinary kallikrein seems to be able to detect a different, and perhaps in certain cases earlier, effect of lead intoxication on enzyme functions.