Effect of the Ketogenic Diet on the Activity Level of Wistar Rats

Abstract

Children, adolescents, and adults with epilepsy often also show symptoms associated with attention-deficit/hyperactivity disorder (ADHD). The ketogenic diet, which is administered to children with epilepsy refractory to drug therapy, seems to improve behavior in individuals with symptoms of ADHD. The basis for this improvement is unknown, although it seems to be unrelated to seizure control. The present research was designed to investigate the effect of two ketogenic diets on the behavior of normal adult male rats. Two experiments were conducted. In experiment 1, 36 subjects were placed on one of three diets: a control diet, a 6.3:1 ketogenic diet, and a 4:1 ketogenic diet. In experiment 2, 20 subjects were placed either on a control diet or on a 4:1 ketogenic diet. The activity level of each subject was measured using an open field test. Time spent immobile, grooming, and in exploratory behavior was measured for 600 s. Subjects were tested once before initiation of the diets and once while on the diets. No significant group differences were found in activity level before initiation of the diets. After initiation of the diets, subjects in both ketogenic groups showed a significantly lower activity level than the rats on the control diet. The ketogenic diet decreases activity level in an animal model. This behavioral change may relate to the improved behavior seen when children with symptoms of ADHD are placed on the diet. Attention-deficit/hyperactivity disorder (ADHD) affects children, adolescents, and adults. The symptoms of the disorder include inattentiveness, impulsiveness, and overactivity (1). The cause of the disorder is unknown, although there is evidence that it is, in part, heritable (2-4). The most common treatment for ADHD is stimulant medication.Regardless of whether they meet DSM-IV (1) criteria for the disorder, children and adults with epilepsy often exhibit symptoms of ADHD (5-10). Both anecdotal reports (6,11) and controlled studies (12) suggest that the ketogenic diet ameliorates symptoms of ADHD in individuals with epilepsy. Attention (6,11), cognition (12,13), and behavior (6,11,12) have been reported to improve in individuals who have epilepsy and are on the ketogenic diet. The improvement in these domains seems to be unrelated to the level of seizure control attained (6).The ketogenic diet is a high-fat, low-carbohydrate, and low-protein diet (14,15). It is an effective treatment for intractable epilepsy (5,11,12) and has been found to be useful in controlling seizures that have proved to be unresponsive to drug treatment in both children and adults (15,16). The ketogenic diet has also been found to be effective in animal studies. It increases seizure threshold in several animal models of epilepsy (17)(18)(19). Although the mechanism by which the diet controls seizures is unknown, it is thought that the low level of carbohydrate in the diet forces the brain to take up ketone bodies instead of glucose as a fuel (15,20,21).In the present research, the effect of two different ketogenic diets...

Circadian distribution of generalized tonic–clonic seizures associated with murine succinic semialdehyde dehydrogenase deficiency, a disorder of GABA metabolism

“…This raises an important question regarding the possible effects of a high-fat diet in wild-type littermates and whether this dietary modification might have influenced the behavior of the mutants. Burnham and co-workers conducted a series of studies on the effects of different KD formulas on locomotor activity in different strains of rats [15,16]. Diets with fat:carbohydrate plus protein ratios of 6.3:1, 4:1 (present study also), and 3:1 resulted in a reversible decrease in exploratory activity unrelated to anxiety, sedation, or ataxia.…”

Ketogenic diet attenuates spatial and item memory impairment in pentylenetetrazol-kindled rats

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Ketogenic diet decreases circulating concentrations of neuroactive steroids of female rats

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