The proposed experiments will measure the plastic responses of a highly conserved neuroendocrine circuit necessary for reproduction using an ideally suited model system, the African cichlid fish, Astatotilapia burtoni. In male A. burtoni, social status regulates reproduction via gonadotropin releasing hormone (GnRH1) neurons in the pre-optic area of the brain. The size, dendritic extent and activity of these neurons increase in dominant, reproductively active males and decrease in non dominant males. These social status-induced changes in GnRH1 neurons are well known, however the functional changes that occur during this social conversion are not. To map the functional changes, I will trace neuronal inputs to GnRH1 neurons, comparing those of sexually competent dominant males with those of sexually immature non dominant males. I will also perform a high resolution histochemical analysis of neurotransmitters that influence GnRH1 neurons in each type of male. I will use a novel new technique, array tomography, that allows repeated immunocytochemical labeling on the same brain sections. Understanding the neural plasticity induced by social status change in this uniquely suited model organism will identify the mechanism through which social behavior controls neuronal plasticity of the reproductive system. Sexual maturation is an important biological development that prepares an organism for reproductively active adult life stages. The brain integrates complex social and environmental information to initiate and manage the neural and hormonal changes that support this event. As the GnRH1 system controls reproductive output and fertility in all vertebrates, including humans, understanding the mechanisms that control plastic changes in the reproductive structures of the brain may lead to improved therapies for reproductive disorders, and improve public health.

Agency
National Institute of Health (NIH)
Institute
Eunice Kennedy Shriver National Institute of Child Health & Human Development (NICHD)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
5F32HD063234-02
Application #
8212603
Study Section
Special Emphasis Panel (ZRG1-F03A-F (20))
Program Officer
Lamar, Charisee A
Project Start
2010-01-28
Project End
2013-01-27
Budget Start
2011-01-28
Budget End
2012-01-27
Support Year
2
Fiscal Year
2011
Total Cost
$48,398
Indirect Cost
Name
Stanford University
Department
Biology
Type
Schools of Arts and Sciences
DUNS #
009214214
City
Stanford
State
CA
Country
United States
Zip Code
94305
Fernald, Russell D (2014) Cognitive Skills Needed for Social Hierarchies. Cold Spring Harb Symp Quant Biol 79:229-36
Carpenter, Russ E; Maruska, Karen P; Becker, Lisa et al. (2014) Social opportunity rapidly regulates expression of CRF and CRF receptors in the brain during social ascent of a teleost fish, Astatotilapia burtoni. PLoS One 9:e96632
Loveland, Jasmine L; Uy, Natalie; Maruska, Karen P et al. (2014) Social status differences regulate the serotonergic system of a cichlid fish, Astatotilapia burtoni. J Exp Biol 217:2680-90
Maruska, Karen P; Carpenter, Russ E; Fernald, Russell D (2012) Characterization of cell proliferation throughout the brain of the African cichlid fish Astatotilapia burtoni and its regulation by social status. J Comp Neurol 520:3471-91
Grone, Brian P; Carpenter, Russ E; Lee, Malinda et al. (2012) Food deprivation explains effects of mouthbrooding on ovaries and steroid hormones, but not brain neuropeptide and receptor mRNAs, in an African cichlid fish. Horm Behav 62:18-26