The effect of electroconvulsive shock on food intake and hunger drive in the rat.

Abstract

Many studies have used food-motivated maze running to assess the effects of electroconvulsive shock (ECS) on learning and retention. These studies have generally assumed that an impaired maze performance results only from the effects of the shocks on the cerebral functions subserving learning and retention. However, if hunger drive is decreased as a result of shock, an impairment in performance may occur independently of the cerebral effects. That hunger drive may indeed be affected is suggested in the studies of Bernberg (1) and Jensen and Stainbrook (6), who report alterations in the eating behavior of the rat following a series of ECS's. Neither of these studies, however, was designed specifically for the purpose of investigating the effect of ECS on hunger drive.The study reported here did so, two chief considerations determining the experimental plan. First, since Miller, Bailey, and Stevenson (8) had demonstrated that in rats with lesions in the hypothalamus increased food intake is associated with decreased hunger drive, and since Hoyt and Rosvold (5) had implicated the hypothalamus in the effects of ECS, it was necessary to measure separately the effects of ECS on food intake and hunger drive. Second, ECS in the rat results in decreased activity which may affect eating in two ways: an inactive animal requires less food; the activity of consuming food may be subject to the same reduction as is spontaneous locomotion. Therefore, activity measures were made coincident with the measures of eating behavior. METHOD AnimalsTwenty-two 160-day-old male albino rats of the Sprague-Dawley strain were housed individually either in separate cages or in activity wheels. They were weighed and then fed at the same time each morning

Conflict versus consolidation of memory traces to explain "retrograde amnesia" produced by ECS.

“…Additional support is suggested by the weight data. It has already been observed by Mirsky and Rosvold (1953) that for at least the first 10 days of a series of daily ECS treatments rats on ad lib. food and water show a marked decrement in weight gain as compared with normals.…”

Physiological Psychology

“…There is further evidence that, in domesticated rats, EeS may affect drive states, but the situation is complex. Mirsky & Rosvold (96) have shown that food intake in rats was reduced for as long as 10 days after a series of EeS, if the animals were kept on ad libitum feeding throughout the experimental period. But in rats kept at 85 per cent body weight, during and after EeS, there appears a significant increase in food intake (as soon as they are given free access to food), and there is a corre sponding increase in hunger "drive," if measured by bar-pressing for a food reward.…”

Does electroconvulsive shock therapy work through opioid mechanisms?

“…Daily intakes remained suppressed for 3-4 days following the ECS treatment, and body weights were still depressed when measured 6 days post-ECS (Layden and Birch, 1969). Food consumption and body weights were also reduced both during and/or after a course of ECS (Mirsky and Rosvold, 1953;Coons and Miller, 1960;Pryor, 1974;Belenky and Holaday, 1981). The discrepant reports of the effects of ECS on appetite and body weight are probably due to differences in experimental methods.…”