Lead intoxication during development: its late effects on kidney function and blood pressure

Exposure to lead in early life may result in chronic renal disease in adulthood. To test this hypothesis, we gave Sprague-Dawley rats, from 3 to 9 weeks of age, either tap water or a 1% lead acetate solution, and we studied them (in pairs) 3 and 16 weeks after exposure; that is, at 12 and 25 weeks of age. Lead-intoxicated animals failed to grow. Their GFR's were lower compared with the matched controls and fell between 12 and 25 weeks of age from 4.8 +/- 0.3 to 3.3 +/- 0.4 ml/min/g dry kidney wt (P less than 0.01). Changes in RBF and single nephron GFR were proportional to changes in total kidney GFR, indicating that superficial and deep nephrons were equally affected. The blood pressure in the lead-exposed animals studied at 25 weeks of age was 143.2 +/- 3.7 mm Hg, a value significantly higher than that of 130.4 +/- 3.3 observed in controls (P less than 0.05). These results demonstrate that limited exposure to lead during development can result in progressive renal insufficiency and hypertension.