Changes in brain ATPases in rats fed on chlordane mixed with iron-sufficient and deficient diet.

The in vivo effects of chlordane on brain Na+-K+, oligomycin-sensitive (O.S) and oligomycin-insensitive (O.I) Mg2+ ATPases in rats were investigated. The rats were fed on 0, 25, 50 and 100 ppm chlordane mixed with iron-sufficient (I.S) and deficient (I.D) diets for 12 weeks. The enzyme activities were determined in the brain P2 fraction of rats at the end of 4, 8 and 12 weeks after treatment. Na+-K+ ATPase activity was reduced in a dose-dependent and time-dependent manner in rats fed on chlordane mixed with I.S and I.D diets. The reduction in the enzyme activity was more pronounced in the rats fed on chlordane mixed with I.D diet as compared to those fed on I.S diet. The brain O.S Mg2+ ATPase was also reduced in rats receiving chlordane. The reduction of O.S Mg2+ ATPase was higher than Na+-K+ ATPase. However, the O.I Mg2+ ATPase activity in rats fed on chlordane was not altered at any dose level. These results indicate that the rat brain ATPases may be particularly sensitive to chlordane.