Vitamin A in Oranges. 



187 



animals rhythmic progression was very poorly established. The 

 progression of the animals was much slower and more difficult. 

 The muscles showed frequent tremblings and especially the 

 muscles of the hind legs showed marked weakness. This was not 

 exhibited by control rats in which laparotomy was performed but 

 in which the prostates were not excised. In this second group 

 of animals, futhermore, a marked improvement in muscular 

 efficiency was manifested after feeding of dried prostate and 

 certain other glands, which will be described more fully in the 

 complete paper to appear in the Journal oj Urology. 



87 (1834) 

 Vitamin A in oranges. 



By THOMAS B. OSBORNE and LAFAYETTE B. MENDEL. 



[From the Laboratory of the Connecticut Agricultural Experiment 

 Station and the Sheffield Laboratory of Physiological 

 Chemistry, Yale University, New Haven, Conn.] 



In an earlier paper dealing with citrus fruits 1 we stated that 

 preliminary tests indicated that dried orange juice contains some 

 vitamin A. This conclusion was based on the fact that when 

 the equivalent of 10 c.c. juice was furnished daily to rats on a 

 diet practically devoid of vitamin A, the symptoms which char- 

 acteristically ensue upon such a dietary regime did not develop 

 within the period of 190 days during which our observations 

 continued. For example, the now well known ophthalmia 2 was 

 either cured or averted. 



A reinvestigation of the subject has substantiated our earlier 

 conclusion. In a number of rats maintained on a diet consisting 

 of casein, starch, lard and salt mixture, 3 together with 0.2 gm. of 

 dried breweiy yeast as a source of vitamin B, the characteristic 

 ophthalmia associated with a lack of vitamin A was completely 

 cured within a few days after the daily administration of either 

 10 c.c. of fresh orange juice or the same amount of juice desiccated, 

 admixed with starch, in a current of hot air. Five c.c. of juice 



1 Osborne and Mendel, J. Biol. Chem., 1920, xlii, 465. 



2 Osborne and Mendel, Am. Med. Assn., 1921, lxxvi, 905. 



3 Osborne and Mendel, J. Biol. Chem., 1919, xxxvii, 572. 



