HOWARD T. KARSNER 975 



An abrupt fall of blood pressure in anaphylactic shock is common to all animals but is 

 specially pronounced in the dog and cat (Biedl and Kraus,' Pearce and Eisenbrey,^ Schultz^). 

 The rabbit often shows an evanescent preliminary rise of pressure before the fall. The de- 

 tailed studies have been principally upon the dog and cat. Biedl and Kraus, and Pearce and 

 Eisenbrey, maintained that the heart is not primarily at fault. The fact that injury to the 

 cat's heart has been reported (Edmunds)'' loses some of its significance when it is recognized 

 that the non-sensitized heart also responds in the same qualitative way to serum. Cardiac 

 arrythmias in the dog and rabbit (Auer and Robinson,^ Robinson and Auer*) are not as- 

 sumed by these authors to be the cause of the fall in blood pressure. The vasomotor center 

 is not concerned in the fall (Sollmann) .^ Peripheral vasodilatation has been assumed to be 

 the cause, but the vessels respond to epinephrin and barium (Sollmann). Manwaring, Chil- 

 cote, and Hosepian/ by perfusion experiments, find peripheral vasoconstriction, with oc- 

 casional vasodilatation in the hind extremities. Increased permeability of capillaries, as 

 demonstrated by Manwaring and his colleagues,' indicated also by the work of Peterson and 

 his collaborators'" showing increase in flow and protein content of the lymph, may be in part 

 responsible. Much attention has been given to the return flow of blood to the heart. In gen- 

 eral, this is reduced, although in the cat Edmunds" found no depression of pulmonary-vein 

 pressure and occasionally an increase. Mautner and Pick^^ suggested that decreased return 

 is due to contraction of portal vessels. Manwaring'^ and subsequently Voegtlin and Bern- 

 heim^'' found that exclusion of the liver prevents the occurrence of anaphylactic shock. Pelz 

 and Jackson's state that exclusion of the entire abdominal circulation does not prevent 

 shock. Simonds,'^ however, and Manwaring,'^ continue to assert the significance of the liver, 

 and that view is generally accepted. The explanation of the influence of this organ differs 

 with the two latter investigators. By pressure on the portal veins, Manwaring was able to 

 produce a fall in systemic blood pressure but maintains that the rise in portal pressure is not 

 sufficient to account for the fall in systemic pressure in peptone shock. By compression of 

 the hepatic vein, Simonds'^ finds that the mechanical disturbance is sufficient to explain the 

 systemic change in peptone and anaphylactic shock. The latter experiment is more in ac- 



' Biedl, A., and Kraus, R.: Wien. klin. Wchnschr., 22, 363. 1909. 



^ Pearce, R. M., and Eisenbrey, A. B. : /. Infect. Dis., 7, 565. 1910; Eisenbrey, A. B., and Pearce, 

 R. M.: /. Pharmacol. &" Exper. Tkerap., 4, 21. 1912. 



•5 Schultz, W. H.: /. Pharmacol, b" Exper. Therap., 3, 299. 191 2. 



^Edmunds, C. W.: loc. cil. 



5 Auer, J., and Robinson, G. C: /. Exper. Med., 18, 450. 1913. 



* Robinson, G. C, and Auer, J.: ibid., p. 556. 1913. 



'Sollmann, T.: Manual of Pharmacology (3d ed.), p. 484. Philadelphia: Saunders, 1926. 



* Manwaring, W. H., Chilcote, R. €., and Hosepian, V. M.: /. Immunol., 8, 233. 1923. 

 'Manwaring, W. H., Chilcote, R. C, and Hosepian, V. M.: J. A.M. A., 80, 303. 1923. 



'"Peterson, W. S., Levinson, S. A., and Hughes, T. P.: /. Immunol., 8, 323. 1923. 

 " Edmunds, C. W.: loc. cit. 



" Mautner, H., and Pick, T.: Miinchen. med. Wchnschr., 62, 1141. 1915. 

 '3 Manwaring, W. H.: Ztschr.f. Immunildtsforsch. u. exper. Therap., 8, i. 1910. 

 "• Voegtlin, C, and Bernheim, B. M.: J. Pharmacol. &° Exper. Therap., 2, 507. 1911. 

 '5 See Pelz, M. D., and Jackson, D. E.: loc. cil. 



'^Simonds, J. P.: Am. J. Physiol., 65, 512. 1923; Simonds, J. P., and Brandes, W. W.: ibid., 

 72, 320. 1925. 



'7 Manwaring, W. H., Brill, S., and Boyd, W. H.: J. Immunol., 8, 121. 1923. 

 ■^ Simonds, J. P.: J. A.M. A., 73, 1437. 1919- 



