The Effects of Ablation of the Septal Nuclei in the Rat on Circadian Variation and Stress Response Pattern of Corticosterone, Growth Hormone and Prolactin

It has long been known that destruction of the septal nuclei in rats is followed by a very dramatic change in affective behavior (3). This change has frequently been dubbed the septal syndrome and is characterized by behavioral overreaction to most environmental stimuli. Once present, however, the septal syndrome is a self-limiting condition observed to persist for postoperative periods of 7–75 days (12,17). Normal attenuation of the syndrome is facilitated by environment stimulation (11,18). One way environmental factors could influence the behavior of septal rats is through the brain-pituitary-endocrine axis as hormones have direct influences on brain activity and behavior (10,13,29).