Seizure resistance is dependent upon age and calorie restriction in rats fed a ketogenic diet

The present study was designed to evaluate the effects of age on the effica cy of the ketogenic diet in suppressing seizures evoked by tail-vein infusi on of pentylenetetrazole (PTZ). Male rats of various ages were divided into three groups and fed one of three diets: (1) a calorie-restricted ketogeni c diet, (2) a calorie-restricted normal (rodent chow) diet, or (3) a normal diet, ad libitum. After animals had been on experimental or control diets for more than 20 days, seizure threshold and blood levels of beta-hydroxybu tyrate (beta-OHB) were determined. Animals fed a ketogenic diet exhibited s ignificant elevations in levels of beta-OHB and seizure resistance compared to animals fed either a calorie-restricted normal diet or a normal diet, a d libitum. The levels of beta-OHB and seizure resistance were greatest for young pups. A surprising finding was that young animals fed a calorie-restr icted rodent chow diet exhibited a significantly increased resistance to se izures compared to those fed the same diet, ad libitum. Results presented h ere demonstrate that the ketogenic diet produces the highest levels of keto nemia and seizure threshold in young animals. Collectively, these data sugg est that age and caloric restriction are important considerations for imple menting the ketogenic diet. (C) 1999 Elsevier Science B.V. All rights reser ved.