206 INTERNAL SECRETION 



peristaltic movements of the ureters are not influenced either by 

 adrenalin or by stimulation of the sympathetic. In spite of the 

 close relationship between the Mustelides and Herpestes mungo, 

 the bladder of the latter does not react to adrenalin. The urinary 

 bladder of goats and of the Indian civet-cat (Viverra zibetha) 

 responds in the same manner as that of the ferret. 



This difference in the innervation of the bladder in mammals 

 serves to show very clearly that adrenalin may exercise an 

 inhibitory action upon unstriated muscles, if these muscles receive 

 an inhibitory innervation from the sympathetic. The muscular 

 inhibition produced by adrenalin is entirely independent of the 

 blanching provoked by this substance ; for, in the cat, the latter 

 effect is almost entirely absent, while the relaxation of the 

 muscles is perceptible in every part of the bladder, and may be 

 produced by direct local application. 



That the specific action of adrenalin is, in the case of certain 

 tissues, independent of the blanching process, is also seen in the 

 heart, where the coronary vessels remain uninfluenced, while 

 the rapidity and strength of the contractions is considerably 

 increased. The direct effect of adrenalin independently of the 

 blood supply, namely, relaxation and cessation of spontaneous 

 movements, may also be observed in a portion of living intestinal 

 wall after its removal from the body. 



The External Genital Organs. After the intravenous injec- 

 tion of suprarenal extract, these organs become blanched and 

 contract in a manner similar to that which follows stimulation of 

 the lumbar sympathetic (Langley and Anderson). The tunica 

 dartos of the testicle has a different reaction it does not contract 

 in response to suprarenal extract. According to S. Lieben, the 

 intravenous injection of adrenalin provokes relaxation of the 

 tunica dartos. 



The Internal Genital Organs. Langley observed a high 

 degree of contraction and marked blanching of the vagina and 

 cornua in rabbits and cats, after the intravenous injection of 

 .adrenalin in small doses. In male animals, there was a contrac- 

 tion of the vas deferens. 



The similarity between the effects of adrenalin upon the uter- 

 ine muscles, and those of stimulation of the sympathetic, will be 

 fully discussed later. For the present purpose, the following 

 will suffice. 



The effect which adrenalin has upon the uterus is among 

 the most perfect and startling of the phenomena which this 

 remarkable substance calls forth. The blanching and contrac- 

 tion are well seen in the virgin uterus, but these appearances 

 are nothing short of astonishing in the uterus of the pregnant or 

 puerperal animal observed in a normal saline bath. The 

 intravenous injection of adrenalin produces a degree of uterine 

 .anaemia and a violence of contraction, not obtainable by the 



