Effects of medial prefrontal cortex lesions on anxiety-like behaviour in restrained and non-restrained rats.
The medial prefrontal cortex has been associated with fear, anxiety and stress regulation, and has recently been suggested to play a crucial role in the development of behavioural changes in response to stress. In this study, we evaluated medial prefrontal cortex (mPFC) involvement in both anxiety-like behaviour and increased anxiety-like responses induced by uncontrollable restraint. Rats with mPFC electrolytic lesions (n=7) and sham-lesioned (n=8) were tested in the elevated T-maze (ETM). Restrained rats with mPFC lesions (n=8) and sham-lesioned rats (n=6) were tested in the elevated T-maze 24h after restraint. Both two-trial passive avoidance and one-trial escape behaviours were assessed. The results revealed that mPFC lesions impair passive avoidance, but not escape behaviour. In addition, decreased anxiety-like behaviour in both passive avoidance and escape behaviours were observed in restrained rats with mPFC lesions. Our results suggest that mPFC is important in mediating both anxiety-like behaviour expression and long-term anxiogenic-like effects induced by acute restraint.
Departamento de Psicobiología y Metodología de las CC, Universidad Málaga, Campus de Teatinos s/n, Málaga CP 29071, Spain.
Eduardo
E
Blanco
Estela
E
Castilla-Ortega
Rubén
R
Miranda
Azucena
A
Begega
José A
JA
Aguirre
Jorge L
JL
Arias
Luis J
LJ
Santín
D000818:Animals; D001007:Anxiety / Q000209:etiology / Q000503:physiopathology*; D001522:Behavior, Animal / Q000502:physiology*; D004924:Escape Reaction / Q000502:physiology*; D005106:Exploratory Behavior; D008297:Male; D018782:Maze Learning; D017397:Prefrontal Cortex / Q000502:physiology* / Q000503:physiopathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012149:Restraint, Physical / Q000523:psychology; D013315:Stress, Psychological / Q000150:complications / Q000503:physiopathology*