Effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on IgA serum and bile levels in rats.
Serum IgA is actively transported from blood to bile against a concentration gradient in the liver by the binding of dimeric IgA to secretory component, endocytosis and transport to the bile canaliculus by vesicles. As 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has been shown to elicit hepatotoxicity, the effects of TCDD on rat serum and bile IgA levels were investigated. Rats were orally administered 50 micrograms TCDD/kg body weight in 95% corn oil: 5% acetone. At days 5, 10, 15, 20 and 30 after treatment, rats were anesthetized and a cannula inserted into the bile duct for collection of bile. In addition, blood was drawn, and, after euthanasia, the liver and thymus weights were recorded. Enzyme-linked immunosorbent assay (ELISA) techniques were employed to determine IgA in serum and bile and IgG levels in serum. Rocket immunoelectrophoresis was carried out to support ELISA results. It was found that serum IgA increased with time while serum IgG remained unchanged. In addition, while serum IgA levels were increasing, there was a concomitant decrease in biliary IgA. Thymus and liver weight changes were also observed. The data indicate that TCDD affects hepatic clearance of serum dimeric IgA and suggests that liver damage may be reflected by increased serum levels of IgA.
D000818:Animals; D001646:Bile / Q000187:drug effects / Q000276:immunology*; D001835:Body Weight / Q000187:drug effects; D004147:Dioxins / Q000633:toxicity*; D004797:Enzyme-Linked Immunosorbent Assay; D007122:Immunoelectrophoresis; D007070:Immunoglobulin A / Q000032:analysis*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D000072317:Polychlorinated Dibenzodioxins / Q000633:toxicity*; D051381:Rats; D011919:Rats, Inbred Strains; D013950:Thymus Gland / Q000033:anatomy & histology
D004147:Dioxins; D007070:Immunoglobulin A; D000072317:Polychlorinated Dibenzodioxins