Gastric pathology and aphagia following lateral hypothalamic lesions in rats: Effects of preoperative weight reduction.

Abstract

The body weights of male albino rats were reduced gradually to 80% of normal body weight by restricting food intake (dieting), and then the rats were given lateral hypothalamic (LH) lesions. Compared with rats of normal body weight sustaining similar brain lesions, the dieted group displayed a shorter period of postoperative aphagia and less gastric pathology. In a second experiment, a group of rats was reduced to 80% of normal body weight by withholding all food (fasting) and then given LH lesions. Compared with dieted rats sustaining similar brain damage, the fasted group displayed a longer period of postoperative aphagia and greater gastric pathology. Since the duration of aphagia could be shortened or lengthened by simple manipulations of preoperative body weight, the adequacy of sensorimotor or motivational hypotheses to account for aphagia is questioned. The results are more consistent with the suggestion that gastric abnormalities produced by LH lesions inhibit eating. This research was supported by Grant MRan( j the orientation to somatic and olfactory w 13 ^^ K the N , at . ional Institute of Mental ^^^j ( Marsha n & Teitelbaum, 1974; Health and by an Arizona State University Fac-,, , " ^ e ^ -x iu im-i ulty Grant-In-Aid Award to Ernest Lindholm. Marshall, Turner, & Teitelbaum, 1971; Experiment 1 was the master's thesis of Carlos Turner, 1973). These dysfunctions have Grijalva, who was supported by a Ford Founda-been referred to as sensory neglect (Marshall tion Graduate Fellowship. The authors thank J. e t & \ 1971), sensory inattention (Marshall J %™ t f 7 helpfUl t Cri l iCiS M S K ** if * & Teitelbaum, 1974), or the sensorimotor Requests for reprints should be sent to Ernest , /m ' ,«""•> CT --i

Long-Lasting Functional Disabilities in Middle-Aged Rats with Small Cerebral Infarcts

“…This sustained the animals at ϳ400 gm, which is only slightly less than the 450 gm average weight expected for F-344 rats maintained on ad libitum feeding. Although this does not represent a severe degree of caloric restriction, and this restricted feeding schedule did not begin until the rats were 10 months of age, it is well known that animals maintained on restricted feeding schedules have lower mortality rates and increased longevity, and it has been reported that recovery from brain injury is faster and more complete in food-restricted rats (Grijalva et al, 1976;Schallert and Whishaw, 1978;Schallert, 1989), even in aged rats (Joseph et al, 1983), and that food-restricted rats suffer fewer complications (Grijalva et al, 1976;Luszawska et al, 1977). Therefore, it is possible that the acceptably low mortality rates seen in the present study may be partly attributable to the use of fairly long-term scheduled feedings.…”

The effects of preoperative ingestive events on feeding and drinking behavior following brain damage

“…If the cortex is removed 10 days before the LH lesion, there appears to be no protective effect (Glick & Greenstein, 1972a). In this regard, note again that abruptly reducing the body weight of rats over aperiod of a few days before LH lesioning does not prOOuce the protective effect (Grijalva et al, 1976).…”

“…When rats are preoperatively dieted, with their body weights abruptly reduced by the elimination of au access to food for 6 days, there is no protective effect (Grijalva et al, 1976). But body-weight set point should be altered, and yet there is no recovery.…”

Body weight reduction prior to quinine adulteration of water: Interactive complexities in measures of ingestive behavior

“…At no time during the study did ND-Q rats display reductions below 97% of their initial weight. In addition, it should be noted that care was taken to guarantee gradual fasting of PD-Q subjects down to the target percentage (Grijalva, Lindholm, Schallert, & Bicknell, 1976).…”