Restricted feeding and its effects on aphagia and ingestion-related disorders following lateral hypothalamic damage

Previous studies have shown that lateral hypothalamic (LH) damage produces aphagia, gastric pathology, hyperthermia, and sensorimotor dysfunctions. Furthermore, preoperative dieting has been reported to shorten the period of aphagia, reduce the incidence of gastric pathology, attenuate the hyperthermia, and facilitate recovery of certain sensorimotor dysfunctions following LH lesions in rats. The present study compared the effects of dieting and two additional restricted feeding regimens (meal feeding alone or in combination with a high-carbohydrate supplement) which produced different body weight functions on several disorders induced by LH lesions. Restricted feeding (i.e., dieting and meal feeding), which resulted in approximately at 5% to 25% drop in body weight prior to LH lesions, similarly shortened the period of postoperative aphagia, reduced the incidence of gastric pathology, prevented the hyperthermia, and facilitated recovery of responsivity to tactile stimulation; however, other sensorimotor dysfunctions were relatively unaffected. Because the initial reinstatement of eating occurred at different body weight levels and in the presence of obvious sensorimotor abnormalities, it is unlikely that either body or sensorimotor dysfunctions per se are critical factors in determining the period of aphagia. The results are more consistent with the view that metabolic disorders that are attenuated by restricted feeding significantly contribute to the ingestive deficits of LH-damaged rats.