PITUITARY-ADRENOCORTICAL RESPONSE TO SHOCK-INDUCED STRESS IN NORMAL AND HYPOTHALAMIC HYPERPHAGIC RATS

Several previous experiments have reported that mediobasal hypothalamic lesions that include the ventromedial nuclei result in decreased adrenal weights and impaired pituitary-adrenocortical responses to stress. In the present experiment, lean and obese rats with lesions of the ventromedial hypothalamus that spared the median eminence were found to have normal adrenal weights and normal elevations in plasma corticosterone to shock-induced stress. The previous results were attributed to incidental damage to adjacent structures, particularly the median eminence. Lean but not obese VMH-lesioned rats were found to have higher baseline corticosterone levels. © 1979.