Exocrine pancreatic pathology in female Harlan Sprague-Dawley rats after chronic treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin and dioxin-like compounds.
We evaluated the effect of chronic exposure to dioxin and dioxin-like compounds on the pancreas in female Harlan Sprague-Dawley rats. This investigation represents part of an ongoing National Toxicology Program initiative to determine the relative potency of chronic toxicity and carcinogenicity of polychlorinated dioxins, furans, and biphenyls. Animals were treated by gavage for up to 2 years with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3,4,4,5-pentachlorobiphenyl (PCB-126), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), or a toxic-equivalency-factor (TEF) mixture of these agents; control animals received corn oil-acetone vehicle alone. A complete necropsy was performed on all animals, and a full complement of tissues was collected and examined microscopically. Administration of each of the four compounds was associated with increased incidences of several nonneoplastic changes in the exocrine pancreas, including cytoplasmic vacuolation, chronic active inflammation, atrophy, and arteritis. Low incidences, but higher than those in the historical database, of pancreatic acinar adenoma and carcinoma were seen in the TCDD, PeCDF, and TEF-mixture groups. These results indicate that the pancreatic acini are target tissues for dioxin and certain dioxin-like compounds. Key words: carcinogenesis, dioxin, furans, inflammation, pancreas, polychlorinated biphenyls.
Nyska
Abraham
A
Laboratory of Experimental Pathology, National Institute of Environmental Health Sciences, National Institutes of Health/DHHS, PO Box 12233, Research Triangle Park, NC 27709, USA. nyska@niehs.nih.gov
Jokinen
Micheal P
MP
Brix
Amy E
AE
Sells
Donald M
DM
Wyde
Michael E
ME
Orzech
Denise
D
Haseman
Joseph K
JK
Flake
Gordon
G
Walker
Nigel J
NJ
D000284:Administration, Oral; D000818:Animals; D004147:Dioxins / Q000008:administration & dosage / Q000633:toxicity*; D004785:Environmental Pollutants / Q000008:administration & dosage / Q000633:toxicity*; D005260:Female; D005663:Furans / Q000008:administration & dosage / Q000633:toxicity*; D007249:Inflammation; D010179:Pancreas / Q000187:drug effects* / Q000473:pathology*; D011078:Polychlorinated Biphenyls / Q000008:administration & dosage / Q000633:toxicity*; D000072317:Polychlorinated Dibenzodioxins / Q000008:administration & dosage / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley
D004147:Dioxins; D004785:Environmental Pollutants; D005663:Furans; D000072317:Polychlorinated Dibenzodioxins; D011078:Polychlorinated Biphenyls