| in vivo and in vitro changes in neurochemical parameters related to mercury concentrations from specific brain regions of polar bears (ursus maritimus). | mercury (hg) has been detected in polar bear brain tissue, but its biological effects are not well known. relationships between hg concentrations and neurochemical enzyme activities and receptor binding were assessed in the cerebellum, frontal lobes, and occipital lobes of 24 polar bears collected from nunavik (northern quebec), canada. the concentration-response relationship was further studied with in vitro experiments using pooled brain homogenate of 12 randomly chosen bears. in environmental ... | 2014 | 25264143 |