Effects of N-methyl- d-aspartate-induced amygdala lesion in rats submitted to the elevated T-maze test of anxiety

• Published in: Physiology & behavior 2003, Vol.78 (1), p.157-163
• Main Authors: Strauss, Christiana V.A, Maisonnette, Silvia S, Coimbra, Norberto C, Zangrossi, Hélio
• Format: Article
• Language: English
• Subjects: Amygdala; Amygdala - pathology; Amygdala - physiology; Anatomical correlates of behavior; Animals; Anxiety - psychology; Behavior, Animal - drug effects; Behavioral psychophysiology; Biological and medical sciences; Elevated T-maze; Excitatory Amino Acid Agonists - toxicity; Fundamental and applied biological sciences. Psychology; Generalized anxiety; Lesion; Male; Motor Activity - drug effects; N-Methylaspartate - toxicity; Panic; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Rats; Rats, Wistar
• ISSN: 0031-9384; 1873-507X
• DOI: 10.1016/S0031-9384(02)00960-5

The elevated T-maze (ETM) has been used to generate two defensive behaviors in the same rat, inhibitory avoidance and one-way escape, which have been related to generalized anxiety and panic, respectively. In the present study, we investigate the role of the amygdala on the modulation of these two behaviors. Male Wistar rats were tested in the ETM test 2, 7, or 14 days after bilateral N-methyl- d-aspartate (NMDA)-induced lesion of the amygdala. The animals were also tested in an open field for evaluation of motor performance. The results showed that animals tested 7 days after NMDA injection had impairment in the acquisition of inhibitory avoidance, indicating an anxiolytic effect. Lesion of the amygdala did not change one-way escape in any of the tested groups. These results provide further evidence for the involvement of the amygdala in the modulation of defensive behaviors that have been associated to generalized anxiety.