The cortical epithelium of the rat thymus after in vivo exposure to bis(tri-n-butyltin)oxide (TBTO). An (immuno)histological and ultrastructural study.
Bis(tri-n-butyltin)oxide (TBTO) induces cortical atrophy in the rat thymus. We studied the potential involvement of the cortical epithelium in TBTO-induced thymotoxicity by (immuno) histology and electron microscopy. Juvenile male Wistar rats were orally intubated once with either 30 or 90 mg/kg TBTO and sacrificed 4 or 10 days later. A dose-dependent thymic atrophy occurred. Anti-keratin labelling showed epithelial cell aggregation in some animals at 10 days after exposure to 90 mg/kg TBTO, when recovery of the thymus was apparent. At the ultrastructural level, a relative shift was observed from "pale" to darker epithelial cell subtypes at the 30 mg/kg dose level, both at day 4 and day 10 after intubation. This phenomenon was not observed after exposure to 90 mg/kg TBTO. Both the altered keratin distribution and the increased electron density of the epithelium probably represent non-specific phenomena. The present morphological observations support the concept that TBTO affects the thymus via its action on lymphoid cells rather than on the epithelial compartment.
De Waal
E J
EJ
National Institute of Public Health and Environmental Protection, Bilthoven, The Netherlands.
Schuurman
H J
HJ
Rademakers
L H
LH
Van Loveren
H
H
Vos
J G
JG
D000818:Animals; D004848:Epithelium / Q000187:drug effects / Q000473:pathology / Q000648:ultrastructure; D007150:Immunohistochemistry; D007166:Immunosuppressive Agents / Q000494:pharmacology* / Q000633:toxicity; D008297:Male; D008854:Microscopy, Electron; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013950:Thymus Gland / Q000187:drug effects* / Q000473:pathology / Q000648:ultrastructure; D014220:Trialkyltin Compounds / Q000494:pharmacology* / Q000633:toxicity
D007166:Immunosuppressive Agents; D014220:Trialkyltin Compounds; C005961:bis(tri-n-butyltin)oxide