140 



Scientific Proceedings (53). 



Summary. — 1. Depressor and pressor substances arise after 

 vaccinia infection in the blood-serum of rabbits. 2. Aging tends 

 to eliminate the depressor substance and a pressor substance then 

 comes in evidence. 



Note. — A serum obtained from a rabbit after streptococcus infec- 

 tion, which had 12 months previously given a profound depressor 

 reaction was also tested (3-1 8-1 3) and was found to give no reac- 

 tion. 8 c.c. of a saline extraction of the adrenals of a 30 day 

 vaccinia rabbit, gave (3-28-13) no reaction. This extraction was 

 made in 20 c.c. of physiological saline solution and was kept 6 

 days in the ice-box. 7 c.c. of a saline extraction of the adrenals 

 of a two day vaccinia rabbit gave (3-8-13) a fine rise followed by 

 a marked fall. This extraction was made in 20 c.c. and was kept 

 24 hrs. in the ice-box, i. e., since immediately after removal. 



Abstracts of the Communications, Pacific Coast Branch. 



Third meeting. 

 San Francisco, California, April 2, 1913. 

 92 (788) 



Preliminary communication on the part played by cholesterol in 

 determining the incidence of carcinoma. 



By T. Brailsford Robertson and Theodore C. Burnett. 



[From the Rudolph Spreckels Physiological Laboratory of the Uni- 

 versity of California.] 



We have elsewhere shown 1 that cholesterol, when injected 

 directly into rat carcinomas, causes a marked acceleration both 

 of the primary and of the metastatic growth of the tumors. 



This led us to form the opinion that cholesterol is probably a 

 factor of importance in determining the incidence of carcinoma. 



It has been shown by Doree and Gardner, Ellis and Gardner, 

 and others 2 that cholesterol is not synthesized by animals, the 



1 T. Brailsford Robertson and Theodore C Burnett, Proc. Soc. Exper. Biol, 

 and Med., 10 (1912), p. 59; Journal of Exper. Med., 17 (1913), p. 344. 



2 C Doree and J. A. Gardner, Proc. Roy. Soc. London, 80 B (1908), p. 227; 81 B 

 (1909), G. W. Ellis and J. A. Gardner, ibid., 81 B (1909), p. 129. 



