Dépôt numérique
RECHERCHER

Consequences of xenoestrogen exposure on male reproductive function in spottail shiners (Notropis hudsonius)

Aravindakshan, Jayaprakash; Paquet, Valérie; Gregory, Mary; Dufresne, Julie; Fournier, Michel; Macrogliese, David J. et Cyr, Daniel G. ORCID logoORCID: https://orcid.org/0000-0002-6566-783X (2004). Consequences of xenoestrogen exposure on male reproductive function in spottail shiners (Notropis hudsonius) Toxicological Sciences , vol. 78 , nº 1. pp. 156-165. DOI: 10.1093/toxsci/kfh042.

Ce document n'est pas hébergé sur EspaceINRS.

Résumé


There is limited information on the physiological consequences associated with exposure to xenoestrogens under field conditions. The objectives of this study were to determine the presence of estrogenic chemicals in the St. Lawrence River and their effects on male reproduction in the spottail shiner (Notropis hudsonius). Hepatic vitellogenin (VTG) mRNA levels in immature shiners indicate extensive estrogenic contamination spanning almost 50 km both upstream and downstream from the island of Montreal. Stages of spermatogenesis were assessed in fish captured at sites having varying levels of estrogenic contamination. In control fish, 95% had testis of either stage IV (50%) or stage V (45%) of spermatogenesis. At Ile Dorval, where VTG mRNA levels are moderate, fish had testes of stage III (38%) and IV (45%) and only 15% of fish were at spermatogenic stage V. In contrast, at Ilet Vert and Ile Beauregard, located in the sewage effluent plume from the City of Montreal and where hepatic VTG mRNA levels are high in fish, none of the fish were at stage V and 8% of fish at Ilet Vert were at stage II of development. Sperm concentration and various motility parameters were significantly lower in shiners from Ilet Vert as compared with those from Iles de la Paix (reference). Histological analyses of testes revealed that more than one-third of the fish captured at sites with the highest estrogenic contamination displayed intersex, a condition in which ovarian follicles were developing within the testis. These data indicate that there is significant estrogenic contamination in the St. Lawrence River that is associated with impaired reproductive function in male fish.

Type de document: Article
Mots-clés libres: xenoestrogen; toxicity; sperm motility; spermatogenesis; intersex vitellogenin
Centre: Centre INRS-Institut Armand Frappier
Date de dépôt: 15 nov. 2024 20:12
Dernière modification: 15 nov. 2024 20:12
URI: https://espace.inrs.ca/id/eprint/14355

Gestion Actions (Identification requise)

Modifier la notice Modifier la notice