Meeting Abstract

P3-24   -   Role of Gonadotropin-Releasing Hormone on Peripheral Visual Plasticity Anselmo, CM*; Teruyama, R; Maruska, KP; Louisiana State University, Baton Rouge, LA; Louisiana State University, Baton Rouge, LA; Louisiana State University, Baton Rouge, LA cansel5@lsu.edu

Visual signals transmit information such as identity and reproductive status which are crucial for reproduction. Reproductive behaviors are influenced by fluctuating hormones through the reproductive cycle, which can affect sensory plasticity of auditory and olfactory systems, but mechanisms responsible for peripheral visual plasticity remain less explored despite the priority of vision in many species. For example, ovulated female Astatotilapia burtoni, an African cichlid fish, rely on visual communication during reproduction and have improved vision compared to non-ovulated females, but the mechanisms remain undetermined. A. burtoni have conserved GnRH neurons in the brain that project directly to the retina, and ovulated females have higher retinal mRNA levels of GnRH receptors compared to non-reproductive females. Further, retinal GnRH receptor levels are positively correlated with female affiliation towards males suggesting GnRH as a mediator for reproductive visual plasticity. How retinal GnRH signaling contributes to this plasticity and resulting adaptive behavior, however, is unknown. To uncover mechanisms for reproductive visual plasticity, we compared GnRH-mediated changes in activity using calcium imaging on retinal slices and found retinal cells in ovulated females are responsive to GnRH. To test how GnRH influences female visual processing and reproductive behavior, we are using intravitreal (eye) injections of GnRH agonist and antagonist into ovulated females prior to reproductive encounters. We quantify post-injection female affiliation behavior including positive, negative, and neutral responses to male courtship. Understanding mechanisms of reproductive visual plasticity will provide insights on the evolution of female reproductive adaptation and how hormonal changes that modify sensory perception can impact fitness.