FIG. 2.

Acute stress produces dendritic retraction in basolateral amygdala (BLA) pyramidal neurons. (A) Reconstructions of representative BLA pyramidal neurons from unstressed vs. stressed rats that were either non-conditioned or underwent fear conditioning and extinction. Neurons are at or near the mean for each group. Scale bar: 50 μm. (B) Total branch number [mean ± standard error of the mean (SEM)] for BLA pyramidal neurons in unstressed (black bars) vs. stressed (gray bars) rats that were either non-conditioned or underwent fear conditioning and extinction. *P < 0.05 relative to unstressed within the behavioral testing condition. †p < 0.05 relative to non-conditioned within the stress condition. (C) Total branch length (mean ± SEM) for BLA pyramidal neurons in unstressed (black bars) vs. stressed (gray bars) rats that were either non-conditioned or underwent fear conditioning and extinction. *P < 0.05 relative to unstressed within the testing condition. †P < 0.05 relative to untested within the stress condition. Unstressed, no conditioning, n = 5. Stressed, no conditioning, n = 4. Unstressed, conditioning and extinction, n = 8. Stressed, conditioning and extinction, n = 10.