Habenula activation patterns in a preclinical model of neuropathic pain accompanied by depressive-like behaviour

Author(s)

Antunes, Geiza Fernanda ; Pinheiro Campos, Ana Carolina ; de Assis, Danielle Varin ; Gouveia, Flavia Venetucci ; de Jesus Seno, Midia Dias ; Pagano, Rosana Lima ; Ruiz Martinez, Raquel Chacon

• Document type: Journal article
• Source: PLoS One; v. 17, n. 7, p. 12-pg., 2022-07-12.

Abstract

Pain and depression are complex disorders that frequently co-occur, resulting in diminished quality of life. The habenula is an epithalamic structure considered to play a pivotal role in the neurocircuitry of both pain and depression. The habenula can be divided into two major areas, the lateral and medial habenula, that can be further subdivided, resulting in 6 main subregions. Here, we investigated habenula activation patterns in a rat model of neuropathic pain with accompanying depressive-like behaviour. Wistar rats received active surgery for the development of neuropathic pain (chronic constriction injury of the sciatic nerve; CCI), sham surgery (surgical control), or no surgery (behavioural control). All animals were evaluated for mechanical nociceptive threshold using the paw pressure test and depressive-like behaviour using the forced swimming test, followed by evaluation of the immunoreactivity to cFos-a marker of neuronal activity-in the habenula and subregions. The Open Field Test was used to evaluate locomotor activity. Animals with peripheral neuropathy (CCI) showed decreased mechanical nociceptive threshold and increased depressive-like behaviour compared to control groups. The CCI group presented decreased cFos immunoreactivity in the total habenula, total lateral habenula and lateral habenula subregions, compared to controls. No difference was found in cFos immunoreactivity in the total medial habenula, however when evaluating the subregions of the medial habenula, we observed distinct activation patterns, with increase cFos immunoreactivity in the superior subregion and decrease in the central subregion. Taken together, our data suggest an involvement of the habenula in neuropathic pain and accompanying depressive-like behaviour. (AU)

• FAPESP's process: 18/18695-9 - Deep brain stimulation and Parkinsons Disease: neuroinflammation control as therapeutic target
• Grantee: Ana Carolina Pinheiro Campos
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 11/08575-7 - The role of dopaminergic modulation in the lateral nucleus of amygdala during active avoidance response
• Grantee: Raquel Chacon Ruiz Martinez
• Support Opportunities: Research Grants - Young Investigators Grants
• FAPESP's process: 13/20602-5 - Prospective analyses of the functional results of philanthropist bilateral amygdalectomy in patients with refractory aggression
• Grantee: Flavia Venetucci Gouveia
• Support Opportunities: Scholarships in Brazil - Doctorate