Fetotoxic action of 2,4-dichlorophenoxyacetic acid (2,4-D). III. Morphological changes in rat kidneys

The paper presents the findings of histological studies on the effect of sodium salt of 2,4-D acid on the changes within kidneys in newborn rats exposed to this herbicide in the prenatal and postnatal period. The experiment was performed on 60 Wistar rats of both sexes, up to 10 weeks of age. The animals were divided into two groups: I group (control)--18 rats fed on a standard diet and given tap water ad libitum, and group II (experimental)--42 rats, whose mothers received sodium salt of 2.4 dichlorophenoxyacetic acid in drinking water at a daily dose of c. 250 mg/kg for 2 months before fertilization and during pregnancy and lactation. The animals were killed after 24 hours, 4, 6 and 10 weeks of the experiment. The sections were taken from the kidneys, fixed in 4% formaldehyde and stained with hematoxylin and eosin. For acid and alkaline phosphatase examination, the kidney section were fixed in Backer's liquid and Gomori histoenzymatic reaction was performed. Histological examination of the first four experimental groups revealed changes in kidney tubules. Histologic changes were nonspecific and a variety of conditions. The presence vacuoles in cytoplasm and necrosis of tubular epithelial cells. Varying degrees of isometric vacuolization of proximal tubular epithelium, tubular microfocal calcification, tubular epithelial inclusion bodies and peritubular capillary congestion were observed. The observations suggest that chronic intoxication with 2,4-D acid leads to renal cell damage in kidneys more intensified in the fetal than in the postnatal period. Following herbicide withdrawal, the most pronounced changes observed in the fetus were found to regress.