1 86 INTERNAL SECRETION 



the contraction is very quickly counteracted by the passive 

 dilatation. 



The effect of adrenalin upon the coronary vessels of the heart 

 is, in one particular, quite distinctive it does not induce con- 

 traction. It will be shown later that strips cut from the 

 coronary vessels react to adrenalin differently from other vessels, 

 and the cause of this startling phenomenon will be explained. 

 It will, moreover, be shown upon which factor the localization of 

 the vascular effects depends. 



The vaso-contraction produced by adrenalin may be observed, 

 in both warm-blooded animals (Pick, Biedl) and in frogs (Lawen), 

 by allowing the substance to circulate through organs removed 

 from the living body (iiberlebend) ; the effect is shown by the 

 marked reduction in the venous outflow. Lawen transfused a 

 liquid composed of two parts suprarenin (Hcechst) to ten million 

 parts Ringer's fluid, through the hinder extremities of Rana 

 esculenta, and he found a reduction of 87 to 96 per cent, in the 

 amount of the outflow; while a solution of ten times less concen- 

 tration produced a reduction of 50 to 81 per cent, in the outflow. 

 If the vessels are washed out with an indifferent liquid, they 

 resume their normal size. Owing to the sensitiveness of this 

 reaction, it is possible to employ artificial circulation through the 

 excised living organ both as a test for the presence of adrenalin 

 and as a means of estimating its physiological value. 



The effect of adrenalin in producing local vaso-constriction is 

 well known and forms the basis of its therapeutic employment. 

 Adrenalin produces a high degree of vaso-contraction in very 

 vascular, and especially in hyperaemic, localities. It was intro- 

 duced into the therapeutics of ophthalmics by Bates and Darier, 

 who employed it as a means for the reduction of the hyperaemia 

 of inflamed and reddened conjunctivas. It has also been employed 

 to produce local anaemia in oto-rhinology and dermatology. The 

 work of H. Braun suggested this substance as an adjuvant to 

 cocaine and its congeners, and it has been largely employed in 

 minor surgery for the production of local anaesthesia. Adrenalin 

 was early employed as a styptic, more especially in paren- 

 chymatous haemorrhage. As early as 1895, I made use of 

 the vaso-contractor properties of adrenalin by employing it in 

 experimental surgery to reduce parenchymatous haemorrhage. I 

 also recommended, and with good result, tampons soaked with 

 sterilized suprarenal extract as a remedy in profuse uterine 

 haemorrhage. To-day, adrenalin is largely employed for the 

 reduction of hyperaemia; as an adjunct to other measures in the 

 production of focal anaesthesia ; for the prevention or reduction of 

 haemorrhage in operation ; and as a styptic. 



Adrenalin is unable to penetrate the epithelial cover, hence 

 it produces no apparent effect upon the normal skin and mucosa as 

 long as these are intact. For therapeutic purposes, adrenalin is 



