5-HT3 receptor within the amygdaloid complex modulates pain hypersensitivity induced by empathy model of cohabitation with a partner in chronic pain condition in mice

Author(s)

Rodrigues Tavares, Ligia Renata ^{[1, 2]} ; Pelarin, Vinicius ^{[1, 2]} ; Baptista-de-Souza, Daniela ^{[1, 3, 4]} ; Pereira Ferrari, Daniele ^[1] ; Nunes-de-Souza, Ricardo Luiz ^{[2, 3, 4]} ; Canto-de-Souza, Azair ^{[1, 2, 4, 5]}

Affiliation

^[1] Univ Fed Sao Carlos UFSCar, Dept Psychol, Psychobiol Grp, CECH, BR-13565905 Sao Carlos, SP - Brazil

^[2] UNESP, Joint Grad Program Physiol Sci UFSCar, Sao Carlos - Brazil

^[3] Univ Estadual Paulista UNESP, Sch Pharmaceut Sci, Lab Pharmacol, Araraquara, SP - Brazil

^[4] Neurosci & Behav Inst IneC, Ribeirao Preto - Brazil

^[5] Program Psychol UFSCar, Sao Carlos - Brazil

• Document type: Journal article
• Source: Social Neuroscience; JUL 2021.
• Web of Science Citations: 0

Abstract

Cohabitation with a partner undergoing chronic pain induces pain hypersensitivity. Among a lot of other neurochemical pathways, the serotonin (5-HT) role, specifically the 5-HT3 receptor (5-HT3R), in the amygdala has never been evaluated in this model. Here we studied the effects of the amygdala's chemical inhibition, its neuronal activation pattern, and 5-HT, 5-HIAA, and 5-HT turnover within the amygdala. Furthermore, the systemic and intra-amygdala 5-HT3R activation and blockade in mice that cohabited with a conspecific subjected to chronic constriction injury were investigated. Male Swiss mice were housed in partners for 28 days. The dyads were divided into two groups on the 14(th) day: cagemate nerve constriction (CNC) and cagemate sham (CS). On the 24(th) day, cagemates underwent a stereotaxic surgery (when necessary) and, on the 28(th) day, they were evaluated on the writhing test. The amygdala inactivation promotes pain-hypersensitivity behaviors in groups and dyads; cohabitation with a partner with chronic pain did not change FosB-labeled cells in the amygdala's nucleus and increases 5-HT turnover in cagemates. Systemic and intra-amygdala 5-HT3R activation attenuated and enhanced the number of writhes, respectively. In contrast, 5-HT3R blockade reduced hypersensitivity pain response. Results suggest the involvement of amygdala serotonergic signaling via 5-HT3R in empathy-like behavior. (AU)

• FAPESP's process: 12/22238-6 - Empathy in mice: role of amígdala, insula and anterior cingulate cortex in the modulation of nociceptive responses
• Grantee: Vinícius Pelarin Do Nascimento Costa
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 17/25409-0 - Neurobiological substrates of the medial prefrontal cortex functional lateralization on defensive reactions induced by social defeat stress in mice
• Grantee: Ricardo Luiz Nunes de Souza
• Support Opportunities: Regular Research Grants
• FAPESP's process: 15/15335-3 - Evaluation of the role of 5-HT3 receptors on nociceptive response in mice subjected to the model of empathy for pain
• Grantee: Daniele Pereira Ferrari
• Support Opportunities: Scholarships in Brazil - Scientific Initiation