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Sex and season influence gonadal steroid biosynthetic pathways, end-product production and steroid conjugation in blotched blue-tongued lizards (Tiliqua nigrolutea)

Citation

Edwards, A and Jones, SM and Davies, NW, Sex and season influence gonadal steroid biosynthetic pathways, end-product production and steroid conjugation in blotched blue-tongued lizards (Tiliqua nigrolutea), General and Comparative Endocrinology, 134, (2) pp. 131-138. ISSN 0016-6480 (2003) [Refereed Article]

DOI: doi:10.1016/S0016-6480(03)00243-0

Abstract

We examined differences in gonadal steroid production and biosynthetic pathway activity with changing reproductive condition and between sexes in the scincid lizard, Tiliqua nigrolutea. We observed clear seasonal and sexual variation in the production of androgens and steroid conjugates, but detected no 17β-estradiol or 5α-dihydrotestosterone produced by the gonads. An alternative steroid, more polar than estradiol, was detected: an investigation of this steroid is reported separately [Gen. Comp. Endocrinol. 129 (2002) 114]. There were seasonal and sex-related differences in steroid biosynthetic pathway activity. The "5 pathway metabolite, dehydroepiandrosterone, was detected only in males, and only from incubations using regressed testicular tissue. There was also a seasonal difference between the sexes in rates of progesterone accumulation, although the absence of corresponding elevated plasma concentrations suggests that the role of progesterone switches from a directly acting hormone to a precursor for others during the reproductive cycle in females. These results suggest that within the traditional view that vertebrate biosynthetic pathway activity and end-products are phylogenetically conserved, there is likely to be considerably species- and/or genus-specific variation. © 2003 Elsevier Inc. All rights reserved.

Item Details

Item Type:Refereed Article
Research Division:Biological Sciences
Research Group:Physiology
Research Field:Animal Physiology - Systems
Objective Division:Expanding Knowledge
Objective Group:Expanding Knowledge
Objective Field:Expanding Knowledge in the Environmental Sciences
Author:Edwards, A (Dr Ashley Edwards)
Author:Jones, SM (Professor Susan Jones)
Author:Davies, NW (Associate Professor Noel Davies)
ID Code:26868
Year Published:2003
Web of Science® Times Cited:3
Deposited By:Zoology
Deposited On:2003-08-01
Last Modified:2007-10-17
Downloads:0

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