Amygdala lesions and 24-h variation in plasma corticosterone, growth hormone, and prolactin levels.

The effects of destruction of the whole amygdala complex on 24-h variations in resting corticosterone, growth hormone, and prolactin levels were investigated in male rats. All three hormones showed the expected resting levels and 24-h variations as previously reported. Bilateral destruction of the amygdala had no effect on either the resting levels or the 24-h variations of these hormones. Thus integrity of the amygdala is not essential for the normal basal and diurnal hormone profile of corticosterone, growth hormone, and prolactin.