New insights on amygdala : basomedial amygdala regulates the physiological response to social novelty.

No Thumbnail Available
Date
2016
Authors
Mesquita, Laura Batista Tavares
Abreu, Aline Rezende Ribeiro de
Abreu, Alessandra Rezende Ribeiro de
Souza, Aline Maria Arlindo de
Noronha, Sylvana Izaura Salyba Rendeiro de
Silva, Fernanda Cacilda dos Santos
Campos, Glenda Siqueira Viggiano
Chianca Júnior, Deoclécio Alves
Menezes, Rodrigo Cunha Alvim de
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The amygdala has been associated with a variety of functions linked to physiological, behavioral and endocrine responses during emotional situations. This brain region is comprised of multiple sub-nuclei. These subnuclei belong to the same structure, but may be involved in different functions, thereby making the study of each sub-nuclei important. Yet, the involvement of the basomedial amygdala (BMA) in the regulation of emotional states has yet to be defined. Therefore, the aim of our study was to investigate the regulatory role of the BMA on the responses evoked during a social novelty model and whether the regulatory role depended on an interaction with the dorsomedial hypothalamus (DMH). Our results showed that the chemical inhibition of the BMA by the microinjection of muscimol (c-aminobutyric acid (GABAA) agonist) promoted increases in mean arterial pressure (MAP) and heart rate (HR), whereas the chemical inhibition of regions near the BMA did not induce such cardiovascular changes. In contrast, the BMA chemical activation by the bilateral microinjection of bicuculline methiodide (BMI; GABAA antagonist), blocked the increases in MAP and HR observed when an intruder rat was suddenly introduced into the cage of a resident rat, and confined to the small cage for 15 min. Additionally, the increase in HR and MAP induced by BMA inhibition were eliminated by DMH chemical inhibition. Thus, our data reveal that the BMA is under continuous GABAergic influence, and that its hyperactivation can reduce the physiological response induced by a social novelty condition, possibly by inhibiting DMH neurons.
Description
Keywords
Social novelty basomedial amygdala, Dorsomedial hypothalamus, Intruder rat
Citation
MESQUITA, L. T. et al. New insights on amygdala: basomedial amygdala regulates the physiological response to social novelty. Neuroscience, v. 330, p. 181-190, 2016. Disponível em: <https://www.sciencedirect.com/science/article/pii/S0306452216302123?via%3Dihub>. Acesso em: 15 set. 2017.