[Frontiers in Bioscience S3, 267-275, January 1, 2011]

Kisspeptins and the neuroendocrine control of reproduction

Victor M. Navarro1,2, Manuel Tena-Sempere2

1Department of Physiology and Biophysics, University of Washington. Seattle, WA, 98185, 2Department of Cell Biology, Physiology and Immunology, University of Cordoba; CIBER Fisiopatologia de la Obesidad y Nutricion; and Instituto Maimonides de Investigaciones Biomedicas de Cordoba (IMIBIC), Cordoba, Spain

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Kisspeptins and reproduction: The missing link
4. Neuroanatomical distribution of Kiss1 and Kiss1R
5. Role of kisspeptin neurons as mediators of sex steroid feedback
6. Interactions of Kiss1 and other neuroendocrine systems at the hypothalamus: The emerging roles of the NKB/NK3R system
7. Conclusions and future lines
8. Acknowledgments
9. References

1. ABSTRACT

Reproductive function, as essential for the survival of species, is under the control of a vast array of regulatory factors that ultimately modulate the release of GnRH. However, GnRH neurons lack the ability to directly sense most of these signals; hence, intermediate pathways are required. Kisspeptins have recently emerged as a pivotal piece in the reproductive brain, serving primarily as conduits for central and peripheral regulatory cues of GnRH release. Different populations of hypothalamic Kiss1 neurons have been described, which mediate either the positive or negative feedback of sex steroids in the sexually differentiated brain of rodents. Kisspeptins, however, are not the only recently-appointed contributors to this integrative process. Indeed, neurokinin B (NKB) and dynorphin have been described to co-localize within Kiss1 neurons at the arcuate nucleus in different species, and may contribute to the regulation of kisspeptin release. In this work, we provide a concise overview of the major reproductive headlines of kisspeptins, focusing on their role as mediators of sex steroid feedback and their interaction with key neurotransmitters, such as NKB and dynorphin.