Titre du document / Document title

Interactive dysmorphogenic effects of toxaphene or toxaphene congeners and hyperglycemia on cultured whole rat embryos during organogenesis

Auteur(s) / Author(s)

CALCIU Cristina ⁽¹⁾ ; KUBOW Stan ⁽¹⁾ ; HING MAN CHAN ^{(1 2)} ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

⁽¹⁾ School of Dietetics and Human Nutrition, MacDonald Campus of McGill University, 21, 111 Lakeshore Road, Ste.-Anne-de-Bellevue, Quebec, H9X 3V9, CANADA
⁽²⁾ Centre for Indigenous Peoples' Nutrition and Environment (CINE), MacDonald Campus of McGill University, 21, 111 Lakeshore Road, Ste.-Anne-de-Bellevue, Quebec, H9X 3V9, CANADA

Résumé / Abstract

Both diabetes mellitus and exposure to environmental contaminants are becoming health hazards to many indigenous populations in the world. In earlier work, we established the embryopathy of the chlorinated pesticide, toxaphene technical mixture (TOX) and its two physiologically most important congeners, T₂ (2-exo,3-endo,5-exo,6-endo,8,8,10,10-octachlorobornane) and T₁₂ (2-exo,3-endo,5-exo,6-endo,8,8,9,10,10-nonachlorobornane). In this study, the combined effects of toxaphene or its two congeners and high glucose concentrations were studied using rat embryo culture in order to investigate the potential interactions between hyperglycemia and toxaphene exposure. Whole rat embryos (0-2 somite) were explanted and cultured into a normal (8 mM) or hyperglycemic 12.5 mM (12.5 G) or 18.75 mM (18.75 G) culture medium containing TOX, T₂, or T₁₂ at various concentrations (0. 100, 1000, 5000 ng ml) for 48 h at 37 °C. All treatments, except mild hyperglycemic exposure (12.5 G), had significant adverse effects on the total morphological score, head and crown-rump length, yolk sac diameter and yolk sac circulation. Embryos exposed to 18.75 G did not show malformations but when hyperglycemia at 18.75 G was combined with higher doses of TOX or T₂ synergistic effects on the incidence of neural tube defects were observed. The embryos cultured with T₁₂ under severe hyperglycemic conditions of 18.75 G showed an inhibition of T₁₂-induced neural tube defects, but there was a concurrent underdevelopment of forelimbs or hindlimbs at the highest T₁₂ dose. The results suggest that there is a site-specific and dose-related interactive dysmorphogenesis elicited by TOX or its congeners with high levels of glucose on rat embryonic development. Because of the relatively high TOX doses used in this study, the drastic growth retardation and malformation observed are unlikely to be observed in human populations. More subtle effects, however, may not be ruled out.

Revue / Journal Title

Toxicology   ISSN 0300-483X   CODEN TXICDD 

Source / Source

2002, vol. 175, n^o1-3, pp. 153-165 (1 p.1/4)

Langue / Language

Anglais

Editeur / Publisher

Elsevier Science, Shannon, IRLANDE  (1973) (Revue)

Mots-clés anglais / English Keywords

Pesticides ; Insecticide ; Organochlorine compounds ; Vertebrata ; Mammalia ; Rodentia ; Mother ; Diabetes mellitus ; Teratogen ; Malformation ; Hyperglycemia ; Embryo culture ; Animal ; Rat ; Toxicity ; Camphechlor ;

Mots-clés français / French Keywords

Pesticide ; Insecticide ; Organochloré ; Vertebrata ; Mammalia ; Rodentia ; Mère ; Diabète ; Tératogène ; Malformation ; Hyperglycémie ; Culture embryon ; Animal ; Rat ; Toxicité ; Camphechlor ;

Mots-clés espagnols / Spanish Keywords

Plaguicida ; Insecticida ; Organoclorado ; Vertebrata ; Mammalia ; Rodentia ; Madre ; Diabetes ; Teratogeno ; Malformación ; Hiperglicemia ; Cultivo embrionario ; Animal ; Rata ; Toxicidad ;

Localisation / Location

INIST-CNRS, Cote INIST : 15984, 35400010152198.0140