IX. PHARMACOLOGY 317 



hibition of growth; this can be prevented by prior soaking of the meal in 

 water, and drying before mixing with the diet J^ ■ ''^ Since formation of HCN 

 was previously shown^'^ to be the most toxic factor in use of the meal, it is 

 not likely that the essential fatty acids are involved. Linoleic acid decreases 

 the synthesis of acetylcholine.''^ Linoleic and linolenic acid deficiency is 

 accompanied by a reduction in time of excitation of peripheral motor nerves 

 and a prolongation of muscular excitation;''^ these aberrances are corrected 

 by treatment with linoleic and linolenic acids. The incidence of ulcers of 

 the gizzard in chicks fed a diet containing cinchophen decreases if methyl 

 arachidonate or the methyl esters of highly unsaturated fatty acids from 

 the phosphatides of beef adrenals are fed.^'' 



E. CHEMOTHERAPY 



Antibiotics from yeasts and Torula utilis are a mixture of unsaturated 

 fatty acids ;^^ that from the mycelia of Penicillium crustosum is linoleic 

 acid;^- and the antibiotic lipid from Tetrahymena geleii is a mixture of un- 

 saturated C22-24 acids.^^ It is probable that other, unidentified antibiotics 

 may ultimately be found to be essential fatty acids. Linoleic and linolenic 

 acids inhibit oxygen uptake by M ycohacterium tuberculosis hominis}^ These 

 acids also inhibit germination of spores of Clostridium botulinum at a con- 

 centration of 1 mg. % but have no effect on vegetative cells; addition of 1 % 

 starch to the medium antagonizes this inhibition.^^ These acids also inac- 

 tivate the neurotropic strain of yellow fever virus, while the virus retains 

 its antigenicity in mice.*^ Fever appears to cause a flooding of unsaturated 

 fatty acids into the blood, and the temporarily beneficial effect of fever in 

 eczema may be related to this.^'^ 



" H. I. MacGregor and J. McGinnis, Poultry Sci. 27, 141 (1948). 



•'s F. H. Kratzer and D. E. Williams, Poultry Sci. 27, 2.36 (1948). 



" R. Vuillaume and J. Gillet, Compt. rend. soc. biol. 136, 614 (1942). 



" C. Torda and H. G. Wolff, Proc. Soc. Exptl. Biol. Med. 59, 246 (1945). 



" R. Lecoq, P. Chauchard, and H. Mazou^, Bull. soc. chim. biol. 29, 717 (1947) . 



scH. Dam, Acta Physiol. Scand. 12, 189 (1946). 



*• E. Uroma and E. A. Virtanen, Ann. Med. Exptl. et Biol. Fenniae (Helsinki) 25, 



36 (1947). 

 82 R. F. Riley and D. K. Miller, Arch. Biochem. 18, 13 (1948). 

 ^ C. M. McKee, J. D. Butcher, V. Group^, and M. Moore, Proc. Soc. Exptl. Biol. 



Med. 65, 326 (1947). 



84 S. Bergstrom, H. Theorell, and H. Davide, Nature 157, 306 (1946). 



85 J. W. Foster and E. S. Wynne, J. Bacteriol. 55, 495 (1948). 



86 G. M. Findlay, Trans. Roy. Soc. Trap. Med. Hyg. 36, 247 (1943). 



87 A. V. Stoesser, J. Allergy 18, 29 (1947). 



