Preview

PDF Restricted - Request a copy 405Kb

In mammals, there is experimental evidence that circulating maternal cortisol is transferred to the embryos across the placenta during gestation. Direct effects of this maternal cortisol may allow embryos to display phenotypic plasticity to cope with postnatal environments (i.e., pre-programming). The potential for maternal hormone induced-adaptation may be of considerable evolutionary significance in viviparous animals. However, to date, there is no such direct evidence that circulating maternal corticosterone passes through the placenta and into the embryos of viviparous reptiles. In this study, we assessed the transfer of (3)H-corticosterone injected into females of the lizard Pseudemoia entrecasteauxii into maternal blood, maternal liver, the embryo, the yolk and the amniotic fluid during mid-to-late gestation. We provide direct evidence that circulating maternal corticosterone passes through the placenta into the embryos in this species. Transfer of maternal corticosterone into the embryos significantly decreased at the end of embryonic development. We discuss these results in terms of the relationships between the degree of corticosterone transfer and embryonic stage. These results demonstrate the potential for direct effects of maternal corticosterone, including endocrine pre-programming, upon the developing embryos in viviparous lizards.

Item Type:	Refereed Article
Research Division:	Biological Sciences
Research Group:	Physiology
Research Field:	Animal Physiology - Systems
Objective Division:	Environment
Objective Group:	Flora, Fauna and Biodiversity
Objective Field:	Forest and Woodlands Flora, Fauna and Biodiversity
Author:	Itonaga, K (Mr Keisuke Itonaga)
Author:	Wapstra, E (Associate Professor Erik Wapstra)
Author:	Jones, SM (Professor Susan Jones)
ID Code:	72076
Year Published:	2011
Web of Science® Times Cited:	8
Deposited By:	Zoology
Deposited On:	2011-08-19
Last Modified:	2017-10-31
Downloads:	1 View Download Statistics