Lysosomal Acid Hydrolases in Primary Monolayer Cultures Derived from Neonatal Brains Exposed Transplacentally to Ethylnitrosourea 1

Abstract

Summary

The effect of transplacental exposure of the fetal rat brain to the carcinogen ethylnitrosourea (ENU) on lysosomal acid hydrolase activities in glial cells has been reported. Primary monolayer cultures of brain cells derived from the brains of newborn rats exposed transplacentally to ENU and from unexposed newborn brains were used to provide concentrated samples of glial cells for hydrolase assay. The hydrolases assayed were β-glucuronidase, N-acetyl-β-D-glucosaminidase, arylsulfatase A and B and acid phosphatase and data were expressed as micromoles of substrate hydrolyzed per hour per milligram of protein. Experimental and control cultures were prepared, incubated and assayed contemporaneously and the ratios between treated and control hydrolase activities were used to evaluate the effect of transplacental ENU exposure.

Results showed that there was no effect on the activities of the lysosomal acid hydrolases measured in primary monolayer cultures of brain cells derived from newborn rat brains exposed transplacentally to ENU. Glucosaminidase activities increased through the 49 day incubation period, while maximum activities of β-glucuronidase, arylsulfatase and acid phosphatase were observed after 21 to 35 days incubation. Hydrolase activities in the brain cell cultures were markedly higher than activities previously reported in neonatal whole brain.