RT Journal Article
SR Electronic
T1 Medial preoptic regulation of the ventral tegmental area related to the control of sociosexual behaviors
JF eneuro
JO eneuro
FD Society for Neuroscience
SP ENEURO.0283-16.2016
DO 10.1523/ENEURO.0283-16.2016
A1 Iyilikci, Onur
A1 Balthazart, Jacques
A1 Ball, Gregory F.
YR 2016
UL http://www.eneuro.org/content/early/2016/12/20/ENEURO.0283-16.2016.abstract
AB During sociosexual encounters, different brain mechanisms interact to orchestrate information about the salience of external stimuli along with the current physiological and environmental conditions in order to process these in an optimal manner. One candidate neural system involves the potential interplay between the medial preoptic nucleus (POM) and mesolimbic reward circuitry. We present here evidence indicating that projections originating from the POM play a modulatory role on the mesolimbic reward circuitry related to male sexual behavior in Japanese quail (Coturnix japonica). First, we utilized an asymmetrical inactivation strategy where POM and VTA were unilaterally inactivated via the GABAA agonist muscimol, either in an ipsilateral or contralateral fashion. Ipsilateral injections of muscimol had negligible effects on both appetitive and consummatory sexual behaviors. In contrast, contralateral injections significantly impaired appetitive sexual behavior, but had no clear effect of consummatory sexual behavior. Next, we labeled cells projecting from the POM to the ventral tegmental area (VTA) by stereotaxic injection in VTA of the retrograde tracer biotinylated dextran amine (BDA). Two weeks later, brains from males who had been allowed to interact freely with a female (15 min) or were kept as controls were collected and fixed for double immunohistochemical labeling of BDA and the immediate early gene Fos. More retrogradely labeled BDA cells in POM expressed Fos after sociosexual interactions than in control conditions. Overall these findings provide novel evidence for the interplay between POM and VTA in the modulation of appetitive but not consummatory sexual behaviors.SIGNIFICANCE STATEMENT: Sociosexual interactions have major costs; reproductive behaviors increase energy expenditure as well as risks of predation and disease. The successful coordination of sociosexual interactions with other activities under complex conditions is therefore closely linked to variation in reproductive success. Optimizing the neural systems mediating this coordination is arguably a key adaptation underlying the evolution of animal populations. The present paper provides novel evidence on how projections from the medial preoptic area to ventral tegmental area of the mesolimbic reward circuitry may play a role in mediating the occurrence of appetitive sexual behaviors.