PHARMACOLOGY OF EPINEPHRINE 127 



the bristles on the scruff of the fox terrier's neck. The hair 

 movement in the macaque is slight on the body but mani- 

 fests itself well over the temples and forehead. The injection 

 of 0.18 mgms. of epinephrine into the mongoose (Herpestes 

 mungo), though insufficient to evoke a maximal dilation of 

 the pupil, nevertheless, causes an extreme erection of the 

 hairs on the animal's tail. The irritability of the arrectores 

 pilorum thus varies directly with their normal functional use. 

 According to Elliott 177 similar considerations are applicable 

 to the varying reaction of other organs. 



The rise of "goose flesh" in the human subject after an in- 

 jection of epinephrine is due to the contraction of the arrectores 

 pilorum. 



MELANOPHORES 



Epinephrine causes contraction of the melanophores of the 

 frog as may be noted by microscopic observation of the effect 

 of painting epinephrine on the web of the foot. The retinal 

 pigment cells migrate distally even in the light, which nor- 

 mally causes their aggregation. In Fundulus heteroclitus, con- 

 traction of the skin melanophores has also been observed in 

 doses as small as 1 to 50 million. This effect is replaced by 

 expansion after a previous injection of ergotoxine. 639 



SECRETIONS 



Epinephrine stimulates the salivary, lachrymal, and other 

 secretions. Since section of the chorda tympani and destruc- 

 tion of the superior cervical ganglion do not interfere with this 

 reaction, the point of stimulation must be peripheral. Other 

 secretions (gastric and mucous secretions of the mouth, esopha- 

 gus, and trachea) are also stimulated. The response of these 

 glands to epinephrine is not marked, however, for the ischae- 

 mia, simultaneously induced, reduces the secretory response 

 to epinephrine. 



Although sweat secretion in the cat's paw is under sympathe- 



