Vitamins B 1 and B 2 in Tissues of Normal and Experimental Rats

Abstract

The relative concentration of Vitamins B₁ and B₂ in normal and experimental rats was determined by feeding dried rat tissue as the source of these vitamins. “Normal rat tissue” was prepared from stock rats, 200-300 gm. in weight. The rats were decapitated, the carcasses (except skin, feet, tail, and intestines) were hashed in a meat grinder and the hashed material was dried in a warm air dryer (50°C.). In the same manner “B₁ rat tissue” was prepared from 20 rats after 30 days on the Evans and Burr diet supplemented with cod liver oil and tikitiki. The average starting and final weights of this group were 186 gm. and 172 gm. respectively, indicating cessation of growth and a loss of weight during the 30-day period on the diet deficient in B₂. “B₂ rat tissue” was similarly prepared from 20 rats after 30 days on the Evans and Burr diet supplemented with cod liver oil and autoclaved liver. The average starting and final weights of this group were 184 gm. and 148 gm. respectively, indicating cessation of growth and a loss of weight during the 30-day period on the diet deficient in B₁. These 3 rat tissue preparations were fed as sources of B₁ and B₂ to young 50 gm. male rats fed the Evans and Burr diet supplemented with cod liver oil and either tikitiki or autoclaved liver.

Normal rat tissue was not a good source of either B₁ or B₂ but was definitely richer in the latter. Better growth resulted with 0.3 gm. of this tissue as a source of B₂ (Group 8) than with 0.7 gm. as a source of B₁ (Group 7).

Normal rat tissue contained more B₁ than either the B₁ or the B₂ rat tissue preparations.

These results were in marked contrast to those obtained when the same tissue preparations were used as a source of vitamin B₂. Normal (Group 8) and B₂ (Group 12) rat tissue were of nearly equal value as sources of B₂.