PLATES CXII AND CXIII THE susceptibility of the young albino rat to the hepatotoxic action of aflatoxin is markedly enhanced by feeding it on protein-deficient diets (Madhavan and Gopalan, 1965). The effect of prednisolone on this form of toxic liver injury is now reported.
MATERIALS AND METHODSTwo experiments, each on a number of test groups as detailed below, were carried out on equal numbers of male and female 28-to 31-day-old stock weanling albino rats, each weighing about 40-50 g. Prednisolone acetate (Deltacortd) in aqueous solution was administered orally with a dropper to each animal in test groups 3,4,5 and 6 (see below); the dosage was 1 mg. per rat per day in experiment 1 and 0.2 mg. per rat per day in experiment 2.Pure crystalline aflatoxin (kindly supplied by Dr P. C. Spensely of the Tropical Products Institute, London) was dissolved in propylene glycol and also given orally with a dropper. Each rat in the test groups 1,2,3 and 4 (see below) received one daily drop containing 70 pg. of the toxin.Two diets were employed and these differed only in protein content, which was 20 per cent. in one and 5 per cent. in the other. The diets were adequate in other nutrients, and included lard ( 5 per cent.), corn starch, vitamin and salt mixtures. The protein source was casein. The detailed composition of the diet is given elsewhere (Madhavan and Gopalan).The different groups of animals in both experiments were given aflatoxin or prednisolone acetate or both, as described above, from the first day, according to the following plan :
Group I-high protein diet +aflatoxin; Group 2-low protein diet +aflatoxin; Group 3-high protein diet +aflatoxin +prednisolone acetate; Group 4-low protein diet taflafoxin +prednisolone acetate: Group 5-high protein diet +prednisolone acetate: Group 6-low protein diet +prednisolone acetate; Group 7-high protein diet alone; Group 8-Iow protein diet alone.Care was taken to allot littermates to comparable groups as far as possible, each group consisting of 8-10 rats.The toxin and the steroid were given immediately before placing the diets in the rat cages.In experiment 1 it was found that there wereno differences between groups 5 and 7 and groups 6 and 8 in respect of growth, food intake and liver histology. Hence groups 7 and 8 were omitted in experiment 2. J. PATH. BACT.-VOL. (1967) 443
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