Effects of Ambient Temperature on Photo-Induced Prolactin Secretion in Three Subspecies of White-Crowned Sparrow, Zonotrichia Leucophrys

From Pubwiki

Jump to: navigation, search

[edit] Author(s)

  • Maney, D. L.
  • Hahn, T. P.
  • Schoech, S. J.
  • Sharp, P. J.
  • Morton, M. L.
  • Wingfield, J. C.

[edit] Journal

General and Comparative Endocrinology 113.3 (1999): 445-56.

[edit] Keywords

white-crowned sparrow prolactin temperature luteinizing hormone gonadal recrudescence starlings sturnus-vulgaris luteinizing-hormone levels vasoactive-intestinal-peptide turkeys meleagris-gallopavo plasma-levels day-length gonadal development reproductive-cycle testicular growth melospiza-melodia

[edit] Abstract

We tested the effects of naturally relevant ambient temperatures (4, 20, and 30 degrees C) on photoinduced prolactin (PRL) secretion in three subspecies of white-crowned sparrow Zonotrichia leucophrys. In all three subspecies, transfer from short to long days triggered an increase in plasma PRL typical of an avian seasonal breeder. In z. l. gambelii, which breeds at high latitudes, temperature does not affect the rate of photoinduced gonadal maturation or luteinizing hormone (LH) secretion. In this subspecies, we found that changes in plasma PRL concentrations were similar in all temperature treatments. In Z. l. pugetensis, which breeds in the Pacific Northwest, high temperatures accelerate gonadal development in females but not males and does not affect LH secretion. In this subspecies, we found that like gonadal growth, photoinduced changes in PRL secretion in z. l. pugetensis vary with ambient temperature in females but not males, In Z. l. oriantha, which breeds in alpine regions of the West, both males and females respond to temperature cues by modulating gonadal growth but not LH secretion. We found in Z. l. oriantha that ambient temperature affects PRL secretion in both sexes. These results suggest that PRL may be involved in the transduction of ambient temperature cues used to time reproductive development and the termination of seasonal breeding. Alternatively, temperature-mediated differences in plasma PRL may be a result rather than a cause of differences in gonadal development, since sex steroids affect PRL secretion in some species. (C) 1999 Academic Press.

[edit] Complete Publication (PDF; password required)

If you would like to join MIGRATE to get access to this publication, please email us!

Retrieved from "http://www.migrate.ou.edu/pubwiki/index.php/Effects_of_Ambient_Temperature_on_Photo-Induced_Prolactin_Secretion_in_Three_Subspecies_of_White-Crowned_Sparrow%2C_Zonotrichia_Leucophrys"