Overeating and obesity produced by interruption of the caudal connections of the hypothalamus: evidence of hormonal and metabolic disruption.

Surgical transection of the posterior connections of the medial basal hypothalamus is much more effective in producing hyperphagia and obesity in female than in male rats. The hyperphagia of female rats can be attenuated by daily injections of estradiol. When starved to the weight of control animals, previously obese female rats with cuts through the posterior hypothalamus showed only mild hyperphagia but quickly returned to their elevated body weights. The results indicated that hormonal and metabolic disturbance are important factors in determining food intake and body weight following damage to the ventromedial hypothalamus.