Gonadotropin-releasing hormone plasticity: a comparative perspective.

Authors

T J Stevenson, Institute for Mind and Biology, University of Chicago, Chicago, IL 60637, United States
T P Hahn, Department of Neurobiology, Physiology, and Behavior, University of California, Davis, United States
S A MacDougall-Shackleton, Department of Psychology, Advanced Facility for Avian Research, University of Western Ontario, Canada
G F Ball, Department of Psychological and Brain Sciences, Johns Hopkins University, United States

Document Type

Article

Publication Date

8-1-2012

Journal

Frontiers in neuroendocrinology

Volume

33

Issue

3

First Page

287

Last Page

300

URL with Digital Object Identifier

10.1016/j.yfrne.2012.09.001

Abstract

Gonadotropin-releasing hormone 1 (GnRH1) is a key regulator of the reproductive neuroendocrine system in vertebrates. Recent developments have suggested that GnRH1 neurons exhibit far greater plasticity at the cellular and molecular levels than previously thought. Furthermore, there is growing evidence that sub-populations of GnRH1 neurons in the preoptic area are highly responsive to specific environmental and hormonal conditions. In this paper we discuss findings that reveal large variation in GnRH1 mRNA and protein expression that are regulated by social cues, photoperiod, and hormonal feedback. We draw upon studies using histochemistry and immediate early genes (e.g., c-FOS/ZENK) to illustrate that specific groups of GnRH1 neurons are topographically organized. Based on data from diverse vertebrate species, we suggest that GnRH1 expression within individuals is temporally dynamic and this plasticity may be evolutionarily conserved. We suggest that the plasticity observed in other neuropeptide systems (i.e. kisspeptin) may have evolved in a similar manner.