Studies on Vitamin B₂ Complex. VII

The Rat Growth Factor in Liver Filtrate, with Evidence for its Multiple Nature

Abstract

In a previous paper, one of us (U. T. ) reported that the rat growth-promoting factor (or factors) in liver filtrate showed great resemblance in properties to factor W of Frost and Elvehjem.
Recently Jukes and Wooley et al. have demonstrated that the “chick antidermatitis factor” is probably identical with pantothenic acid, which has been investigated by Williams and co-workers. But Hoffer and Reichstein, and Subbarow and Hitchings have also indicated that the rat filtrate factor is probably pantothenic acid. Edgar et al. have reported that their liver filtrate factor has at least three components.
Thus it ha s been shown that the so-called “filtrate factor” contains several components which are required for normal growth of rats.
This paper is concerned with the study of the rat growth-promoting substance contained in the different highly purified fractions obtained from liver filtrate.