PROTEIN SENSITIZATION OR ANAPHYLAXIS 317 



from the nicotine was not only lower than that usually 

 seen with such doses, but was much altered in shape, there 

 being a very slow rise in place of the precipitous increase 

 commonly obtained. The injection of nicotine was followed 

 after a short time by a dose of epinephrin which raised the 

 pressure from 22 to 220 mm. Further injections of large 

 doses of the poison were followed by repeated injections 

 of epinephrin which raised the pressure from 18 to 225 mm. 

 These experiments seemed to point conclusively to the 

 nerve endings as being the structure primarily acted upon 

 by the poison, as evidently the receptive substance which 

 is stimulated by the epinephrin had not been paralyzed by 

 the poison. In addition to epinephrin, both digitalis and 

 barium chloride raised the lowered blood pressure very 

 satisfactorily, demonstrating that the muscle cell in these 

 cases was not affected by the doses of poison given. In 

 some animals, however, the use of large doses ,of the poison 

 was followed by a lessened response to epinephrin and 

 digitalis, thus showing that while the nerve ends are first 

 affected, the effect of large doses is not necessarily confined 

 to these structures, but may spread to the receptive 

 substance and contractile substance proper." 



Small doses (25 mg.) of the poison have but little effect 

 upon the heart, beyond a temporary increase in systole and 

 diastole in both auricle and ventricle. This increase is 

 followed in about a minute by some weakening in both 

 chambers, most marked in the auricle, both systole and 

 diastole being decreased. With larger doses (100 to 150 

 mg.) the same changes are produced, the only difference 

 being one of degree. The increase in systole in both auricle 

 and ventricle is quite marked in some cases, while the 

 change in the extent of the dilatation is not so great, but 

 is present in most cases. These changes lead to an increased 

 amplitude of beat which lasts usually from one to two 

 minutes, until the blood-pressure has reached its lowest 

 limit. The fall in pressure coming on while the strength of 

 the beat is increased finds no explanation in the behavior 

 of this organ. 



