The influence of graded doses of vitamin A upon pathological changes in the central nervous system of the rat, with suggestions for a prophylactic assay of the vitamin

Abstract

13 litter-mate series of (80) rats on a vit. A-free diet were given graded doses of vit. A from weaning. After 7 wks. degeneration was found (Marchi technique) in the funiculus praedorsalis of vats receiving 1 LIT. or less per day, but not in those receiving 1.5 I.U. or more. the demarcation being extremely sharp. The simple and rapid procedure might be adapted to form the basis of a prophylactic assay of vit. A.