HYPEKSENSITIVENESS, PROTEIN INTOXICATION 199 



shock has likewise been studied in the rabbit, the cat, the dog, and a few 

 observations have been made upon larger animals. 



When an intoxicating dose of the foreign protein to which a guinea-pig 

 has been sensitized is injected intravenously, there occur in about one min- 

 ute restlessness, bristling of the hair, sneezing and vigorous rubbing of the 

 nose. Within two or three minutes the hind legs become weak. There 

 are violent respiratory efforts accompanied often by convulsive seizures. 

 The animal finally falls on its side, and there are often urination and defe- 

 cation. The respirations become extremely slow and very shallow, and 

 the animal dies. If the dose is not so large, and is not fatal, the symptoms 

 do not usually progress to complete collapse ; the coughing and sneezing and 

 respiratory difficulty are prominent and the pupils are dilated. Gradual 

 recovery ensues, and within a few hours the animal is apparently perfectly 

 well. In the fatal shock the temperature drops, while with smaller or sub- 

 lethal doses, there may be at first a drop and then a rise, in temperature. 



In the rabbit, the respiratory difficulty, which is characteristic of ana- 

 phylactic shock in the guinea-pig, may not be observed, but preliminary ex- 

 citement, later prostration and convulsive seizures and the passage of 

 urine and feces, are very common. The respirations are increased, but 

 the sneezing, coughing and violent respiratory efforts observed in the 

 guinea-pig are absent. Sensitized animals recovering from a sublethal dose 

 of foreign protein may develop a gradually increasing cachexia which may 

 lead to death in a few weeks. It is in the rabbit that Arthus first pointed 

 out that local subcutaneous injections of horse serum, when given every 

 six days in the same site, produce after the fourth and fifth injection, 

 first an edematous infiltration and next the formation of a local gangrene 

 at the point of inoculation. He likewise observed that after four or five 

 injections had been made in the same site, the characteristic local reac- 

 tion could be brought out by an inoculation of the specific protein in any 

 other part of the body. 



In the dog, a re-injection intravenously of the same protein used for 

 sensitization results first in a short stage of excitation lasting scarcely 

 more than a minute. This is followed by swaying and swallowing move- 

 ments and some retching. The animal stands unsteadily, his head and tail 

 down. Very shortly, the retching is followed by vomiting. The animal 

 staggers and falls to the ground. The breathing is not altered or if 

 changed at all, is slow and deep. There are passage of urine and fecal dis- 

 charges which are sometimes bloody. With fatal doses the dog dies in 

 collapse. 



In the cat, great excitement usually follows intravenous injection of 

 the second dose of protein to which the animal is sensitized. Convulsive 

 seizures and paralysis rapidly ensue when a fatal dose is used. The respi- 

 rations are very rapid and difficult, and frequently, frothy material exudes 

 from the mouth. The discharge of urine and feces is common. 



