380 INFECTION AND RESISTANCE 



prevented shock by large doses of chloral hydrate. Rosenau and 

 Anderson, 68 carrying on similar investigations with urethane, paral- 

 dehyd, chloral hydrate, and magnesium sulphate, came to the con- 

 clusion that none of these drugs has any noticeable effect upon ana- 

 phylactic shock in guinea pigs. 



Up to the present time we have confined ourselves to the descrip- 

 tion of the basic anaphylactic experiment, which is spoken of as 

 "active sensitization" in analogy to the expression "active immuniza- 

 tion," since, like the latter, it conveys the conception that the state 

 of hypersusceptibility (like the immunity in active immunization) is 

 here acquired by reason of physiological changes directly induced in 

 the treated animal in reaction to the first injection of the foreign 

 antigen. There is another method of inducing hypersusceptibility 

 which, in continuance of the analogy to immunization, is spoken of 

 as "passive anapliylaxis" since it consists in transferring the hyper- 

 susceptible condition to a perfectly normal animal by injecting into 

 it serum from an actively sensitized one. The normal animal is thus 

 merely the passive recipient of the reaction bodies produced in the 

 sensitive animal by preliminary treatment. 



That such a passive transference of anaphylaxis is possible was 

 shown by a number of investigators almost simultaneously and M. 

 Xicolle, GU in February, 1907, published a study on the phenomenon 

 of Artlms in which he showed that, if the serum of a hypersusceptible 

 rabbit (sensitized with horse serum) was injected into a normal 

 rabbit, the recipient was rendered sensitive, so that the subcutaneous 

 injection of horse serum, made 24 hours later, produced typical 

 infiltrations. Richet 70 soon after this succeeded in transferring 

 hypersusceptibility toward mytilocongestin (a mussel poison) from 

 a sensitized to a normal dog by injecting considerable amounts of the 

 blood from the former into the latter. In this case, too, the hyper- 

 susceptibility of the second dog did not appear until one or two days 

 after the injection of the blood. At almost the same time Otto 71 

 and Friedemann 72 independently succeeded in transferring serum 

 anaphylaxis from hypersusceptible to normal guinea pigs in a similar 

 way. Experiments of Gay and Southard, 73 published during the 

 same year, may possibly be also interpreted as instances of passive 

 anaphylaxis, although their experimental procedure renders this 

 doubtful, even in their own opinions. They injected 0.1 c. c. of 

 serum from both sensitive and refractory guinea pigs into normal 

 animals and followed this, after 10 days, with injections of antigen. 

 The fact that such animals reacted may be interpreted in a number 



68 Rosenau and Anderson. Jour. Med. Res., Vol. 21, N. S., 16, 1909. 



69 M. Nicolle. Ann. de I'Inst. Past., Vol. 21, 1907. 



70 Richet. Ann. de I'Inst. Past., Vol. 21, 1907. 



71 Otto. Munch, med. Woch., No. 34, 1907. 



72 Friedemann. Munch, med. Woch., No. 49, 1907. 



73 Gay and Southard. Jour. Med, Ees., Vol. 16, 1907. 



