THE ANEMIA-PRODUCING PROPERTIES OF α-AMINO-ε-HYDROXYCAPROIC ACID

Abstract

In the course of a new synthesis of lysine, cu-amino+hydroxycaproic acid was isolated as an intermediary compound.lIt was shown that it could not replace lysine in the diet of rats and that it was probably toxic.Upon publication of these original findings,2 Dr.Richard J. Block drew our attention to the probable identity of this compound with the anemiaproducing factor known to exist in deaminized casein.This was investigated.In a first experiment, twenty-one male rats averaging 90 gm. in body weight were put on the following diet: zein 17.4, nL-tryptophan 0.4, soy bean oil 4.0, salts 4.0, cerelose 72, and Cellu flour 2.0 gm. per cent.100 gm. of ration contained thiamine HCl 0.4, riboflavin 0.5, pyridoxine HCl 0.5, calcium pantothenate 3.0, nicotinic acid 3.0, 2-methyl-1,4-naphthoquinone 0.1, inositol 10, and choline chloride 150 mg.After 10 days, the rats were divided into three groups.Group I received 1.5 per cent aamino-e-hydroxycaproic acid and Group II received 1.5 per cent DLlysine, these changes being made at the expense of the cerelose; Group III remained on the basal ration.2 weeks later average hemoglobin values were 8.8, 14.2, and 13.5 gm. per 100 ml. of blood, respectively.Red blood cell counts were as follows: Group I, substituted lysine 2,880,OOO; Group II, nn-lysine 7,790,000, and Group III, no lysine 7,700,OOO.Body weight changes during these 2 weeks were -14, -l-36, and -8 gm., respectively.In a second experiment, 18 per cent casein was substituted for the zeintryptophan fraction of the previous ration and the aminohydroxycaproic acid content was lowered to 1 per cent.Sixteen rats were put on this diet and ten on a control ration.After 17 days, the experimental rats showed an average hemoglobin value of 10.8 gm. per cent and a red blood cell count of 5,610,OOO per cmm., as compared with 13.5 and 8,360,000, respectively, for the control rats.The experimental rats were then divided into four groups, one of them remaining on the previous ration and the other three receiving 1 per cent of a liver concentrate 1 :20, 1 per cent L-lysine, and daily injections of 100 7 of folic acid, respectively.None of these corrective measures proved successful.Average values, 2 weeks later, were hemoglobin 5.5 gm., red blood cells 4,550,OOO per c.mm., and red blood cell volume 26 per cent.The 1