Age-Dependent Effects of Aroclor 1254 super(R) on Calcium Uptake by Subcellular Organelles in Selected Brain Regions of Rats

The in vitro effects of Aroclor 1254 on calcium uptake by microsomes and mitochrondria in cerebellum, frontal cortex, and hippocampus of rats of postnatal days 0, 7, and 21, and as adults were investigated. Significant age-related differences in microsomal Ca uptake was noted in the three brain regions, and some gender-related differences were noted in frontal cortex of postnatal day 21 rats. Differences between the uptake of Ca by microsomes and mitochondria became evident at postnatal day 21 and in adults. At the older ages, the cerebellum had the highest microsomal and mitochondrial Ca uptake. The presence of Aroclor 1254 inhibited Ca uptake by both microsomes and mitochondria at low micromolar concentrations, but the inhibition was age-dependent only in microsomes.