THE EFFECT OF PROLONGED INGESTION OF SYNTHETIC VITAMIN K IN RATS

¹ Laboratories of Northwestern University Dental School and the Department of Biochemistry and Pharmacology, University of Rochester School of Medicine and Dentistry

(1) Eighty-five male and female albino Wistar strain rats were placed on diets containing 0.1, 0.3 and 0.8% menadione.

(2) Diet containing 0.1% menadione produced little, if any, change in growth rate. Diet containing 0.3% menadione produced measurable diminution in growth in male and female rats. A well marked growth rate loss occurred in male rats fed a diet containing 0.8% menadione.

(3) The male rats receiving 0.8% menadione in their diets were found to have a low average RBC count; otherwise these counts and average hemocratic values did not differ in any of the experimental groups from the control values.

(4) On autopsy, the spleens of the male rats which received the highest levels of menadione were very large (twice as heavy as those of control rats) and black in color. Otherwise the organs showed normal average weights, and appeared normal grossly and histologically.

(5) Experimental caries developed equally in rats fed various levels of menadione.