Summary: | 302 p. Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2000. Inorganic Hg was localized through autometallography in beluga hepatic and renal light microscopic sections. Metal grains occurred at high densities in kidney cortical tubular epithelium, with lower densities in medullary tubular epithelium. In liver, metal grain deposition showed marked zonation, accumulating in periportal regions of whales with lower tissue Hg. In belugas with higher hepatic Hg, metal grains were most abundant periportally, but also found pericentrally and midzonally. Metal grains concentrated in stellate macrophages, with much lower numbers in hepatocytic cytoplasm. Staining intensities correlated with tissue concentrations of inorganic, organic, and total Hg. Although hepatic lipofuscin and metal grains were sometimes co-localized, they more often were not. Because marked lipofuscin deposition occurs independent of Hg, causality between hepatic Hg concentration, lipofuscin deposition, and hepatic lesions cannot be inferred.
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