title: Morphometric analysis of osteosclerotic bone resulting from hexachlorobenzene exposure.
abstract: Hexachlorobenzene (HCB) exposure has been shown to induce hyperparathyroidism and osteosclerosis in rats. Experiments were undertaken to investigate the effects of HCB-induced hyperparathyroidism and osteosclerosis on femur morphometry as well as femur breaking strength. Fischer 344 rats were dosed 5 d/wk for 15 wk with 0, 0.1, 1, 10, or 25 mg HCB/kg body weight. Hyperparathyroidism was produced in the two higher dose groups as reported previously (Andrews et al., 1989). Femur weight was significantly increased in the rats receiving 0.1, 1, and 25 mg HCB/kg body weight, whereas density was increased significantly at 1, 10, and 25 mg HCB/kg dose levels. Bone strength was also significantly increased at the three higher dose levels. Cross-sectional area of the midpoint of the femur was significantly increased at the 1 mg/kg HCB dose level. Cortical area and the proportion of the total area of the bone that the cortex occupied were significantly increased at the three higher dose levels. Medullary cavity area was significantly increased at the 0.1 mg/kg dose level but significantly decreased at the 2 higher dose levels of HCB. The right femur was significantly predominant to the left femur in weight, volume, and density through all dosing regimens. HCB exposure significantly altered bone morphometry and strength characteristics in the Fischer 344 rat.
authors.affiliation: Perinatal Toxicology Branch, Environmental Protection Agency, Research Triangle Park, North Carolina 27711.
authors.forename: J E
authors.initials: JE
authors.lastname: Andrews
authors.forename: L D
authors.initials: LD
authors.lastname: Jackson
authors.forename: A G
authors.initials: AG
authors.lastname: Stead
authors.forename: W E
authors.initials: WE
authors.lastname: Donaldson
mesh_terms: D000469:Alkaline Phosphatase / Q000097:blood / Q000652:urine; D000818:Animals; D015519:Bone Density / Q000187:drug effects; D002118:Calcium / Q000097:blood / Q000652:urine; D005269:Femur / Q000187:drug effects / Q000473:pathology*; D006581:Hexachlorobenzene / Q000633:toxicity*; D006961:Hyperparathyroidism / Q000139:chemically induced*; D007770:L-Lactate Dehydrogenase / Q000097:blood / Q000652:urine; D008297:Male; D009929:Organ Size / Q000187:drug effects; D010026:Osteosclerosis / Q000139:chemically induced* / Q000473:pathology; D010758:Phosphorus / Q000097:blood; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D010758:Phosphorus; D006581:Hexachlorobenzene; D007770:L-Lactate Dehydrogenase; D000469:Alkaline Phosphatase; D002118:Calcium