Steroids in the avian brain: heterogeneity across space and time
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Sex steroids influence a diversity of neural and behavioral endpoints in birds, including some that have little to do with reproduction per se. Recent advances in neurochemistry and molecular biology further indicate that the avian brain comprises a network of unique sex steroid microenvironments. Factors involved in steroid synthesis and metabolism are present in the avian brain with expression levels that vary from region to region and with activities that are, in some cases, subject to regulation over relatively slow or rapid time intervals. Advances in our ability to (1) isolate steroids from brain tissue and (2) precisely measure their concentrations reveal how steroid levels vary spatially and temporally. A full appreciation of sex steroid effects on the avian brain require not only measures of hormones in the blood but also an understanding of the numerous and varied mechanisms whereby the brain creates such a heterogeneous steroidal environment.
KeywordsAvian brain Sex steroids Estradiol Dehydroepiandrosterone Testosterone
Supported by NIH MH061994.
- Balthazart J, Ball GF (eds) (2013) Brain aromatase, estrogens and behavior. Behavioral neuroendocrinology. Oxford University Press, OxfordGoogle Scholar
- Charlier TD, Newman AE, Heimovics SA, Po KW, Saldanha CJ, Soma KK (2011) Rapid effects of aggressive interactions on aromatase activity and oestradiol in discrete brain regions of wild male white-crowned sparrows. J Neuroendocrinol 23:742–753. doi: 10.1111/j.1365-2826.2011.02170.x PubMedPubMedCentralCrossRefGoogle Scholar
- Tsutsui K, Inoue K, Miyabara H, Suzuki S, Ogura Y, Tobari Y, Haraguchi S (2009) Discovery of a novel avian neurosteroid, 7alpha-hydroxypregnenolone, and its role in the regulation of the diurnal rhythm of locomotor activity in Japanese quail. Gen Comp Endocrinol 163:117–122. doi: 10.1016/j.ygcen.2009.04.005 PubMedCrossRefGoogle Scholar
- Vanson A, Arnold AP, Schlinger BA (1996) 3B-Hydroxysteroid dehydrogenase/isomerase and aromatase activity in primary cultures of developing zebra finch telencephalon: dehydroepiandrosterone as substrate for synthesis of androstenedione and estrogens. Gen Comp Endocrinol 102:342–350PubMedCrossRefGoogle Scholar
- Wingfield JC, Farner DS (1993) Endocrinology of reproduction in wild species. In: Farner DS, King JR, Parkes KC (eds) Avian biology, vol 9. Academic Press, San Diego, pp 163–327Google Scholar