998 TECHNIQUE OF EXPERIMENTATION IN ANAPHYLAXIS 



Hg. If during the perfusion the lungs are alternately inflated and allowed to collapse 

 by their own elasticity, the rate and degree of pulmonary fixation may be readily fol- 

 lowed. In hypersensitive lungs, incomplete collapse is usually noted within thirty 

 seconds after adding specific foreign protein to the perfusion fluid, with complete 

 pulmonary immobilization by the end of ninety seconds. 



Reactions in the isolated lungs, however, are not always a reliable index to the 

 anaphylactic potentiality of the donor. Typical pulmonary immobilization, for ex- 

 ample, may be demonstrated in the isolated lungs of highly immunized guinea pigs. 



OXYGEN CAPACITY OF BLOOD 



Quantitative determinations of the oxygen content of anaphylactic blood have 

 shown that there is not only a marked reduction in circulating oxygen due to lessened 

 pulmonary ventilation, but a still further reduction due to anaphylactically decreased 

 oxygen-carrying capacity of the blood.^ 



TISSUE RESPIRATION 



Abderhalden and Wertheimer^ have called attention to the possibility of there 

 being an anaphylactically decreased tissue respiration, in addition to the reduced 

 tissue respiration due to decreased circulating oxygen. 



SMOOTH MUSCLE REACTIONS 

 ISOLATED SMOOTH MUSCLE 



The isolated uterus, strips of the urinary bladder, of the intestines, segments of 

 blood vessels, etc., may be tested for their independent anaphylactic potentiality by 

 the Schultz-Dale technique.^ The muscle is suspended in Locke's solution or in one 

 of its modern variants, and the changes in tone following the addition of specific 

 foreign protein to the suspension fluid are recorded. The muscle may be obtained in a 

 relatively blood-free condition by a preliminary perfusion of the hind quarters with 

 Locke's solution. In a typical anaphylactic reaction in an isolated guinea pig uterus, 

 for example, contraction usually starts about fifteen seconds after adding specific 

 foreign protein to the suspension fluid, with maximum contraction usually reached 

 by the end of ninety seconds. 



Smooth muscle reactions thus recorded, however, are not always reliable indexes 



to the anaphylactic potentiality of the animal as a whole. The blood-free uterus of 



highly immunized guinea pigs, for example, will usually give typical anaphylactic 



contraction with the Schultz-Dale technique.'' Non-specific desensitization of the 



entire animal does not always destroy the anaphylactic potentiality of the isolated 



smooth muscle. 



REACTIONS in situ 



The most convenient organ in which to study anaphylactic smooth muscle re- 

 actions in intact animals is the urinary bladder. In dogs, a catheter is tied into the 



' Houssay, B. A., and Cisneros, H. D.: Compl. rend. Soc. de biol., 93, 886. 1925. 

 ^Abderhalden, E., and Wertheimer, E.: Arch.f. d. ges. Physiol., 195,487. 1922. 

 3 Dale, H. H.: J. Pharmacol, b" Exper. Therap., 4, 167. 1913; Matthew, W., and Grove, E. F.: 

 /. Immunol., 10, 498. 1925. 

 f Dale, H. H. : loc. cil. 



