Effect of acetoacetate administration on urinary and tissue vitamin B₆in rats

Abstract

I . Experiments were undertaken to study the effect of daily intraperitoneal injection of acetoacetate for 90 days on vitamin B, status in male albino rats. The initial dose of acetoacetate was 50 mg per kg body-weight, which was increased by 5omg per kg body-weight every 15 days.2. Urinary excretion of vitamin B, was found to decrease after 30 days in acetoacetatetreated rats. After 75 days urinary values of vitamin B, were considerably lower in such rats than in the corresponding control rats.3. When acetoacetate injections were stopped after 90 days and the rats were fed L-tryptophan ( I oomg per rat), they were found to excrete significantlygreater amounts of urinary kynurenine, hydroxykynurenine and xanthurenic acid than the corresponding controls.4. Blood and liver vitamin Be levels were found to be lower in rats treated with acetoacetate for 90 days than in the untreated rats.Prolonged administration of acetoacetate has been previously reported from this laboratory to result in a decrease in urinary and tissue levels of nicotinic acid in rabbits (Nath & Chakrabarti, 1953) and rats (Shastri, Nayudu & Nath, 1967). Shastri et al. (1967) further observed that conversion of tryptophan into nicotinic acid was affected in rats receiving single and multiple injections of acetoacetate. An intraperitoneal injection of acetoacetate was found to result in excretion of abnormally large amounts of urinary kynurenine, hydroxykynurenine and xanthurenic acid in rats fed tryptophan (Nath & Shastri, 1969).Ketone bodies have been found in large quantities after feeding high-fat diets (Khanade & Nath, 1960) and have been thought to be responsible for the deleterious effects of such diets. Kotake (1955) observed pyridoxine deficiency and an increase in urinary and xanthurenic acid excretion in rats given high-fat diets and tryptophan, and also an increase in the ketone bodies in urine of pyridoxine-deficient rats, In the light of these observations, it was thought worth while to study the effect of continued administration of acetoaceate on the vitamin B, status of rats. E X P E R I M E N T A LMale albino rats (40-50 g) were divided into two equal groups of equal mean bodyweight and were fed on a stock laboratory diet consisting of wheat flour 60 %, groundnut oil 9 y 0 , shark-liver oil I yo, casein 20%, Hawk-Oser salt mixture 5 % and yeast 5 %. The food and water were given ad lib.The rats of the second group were injected intraperitoneally with sodium acetoacetate daily; the initial dose was 50 mg/kg body-weight and this was increased by 50 mg/kg every 15 days. Urinary vitamin B, was determined in both groups every https://www.cambridge.org/core/terms. https://doi