ADRENALINE (EttNEPHRlN, ADRENINE) 101 



active on the blood pressure as d-adrenaline, that the effects of the 

 two isomerides on the frog's eye and in producing glycosuria are 

 different, and that d-adrenaline establishes a tolerance to the toxicity of 

 1-adrenaline. Of these experiments those on the frog's eye, by Abder- 

 halden and Thies, and the toxicity experiments, by Abderhalden and 

 Slavu, have been criticised by Schultz [1909, 2]. 



Schultz had previously [1909, i] carried out an extensive series 

 of very careful experiments on the relative activity of racemic and 

 1-adrenaline ; it is a matter for regret that he was not also in possession 

 of a pure specimen of the dextro- variety. He found the pressor effect 

 of the natural base to be one and a half times that of the racemic syn- 

 thetic product. Dale (Barger and Dale, 1910, i] obtained the same 

 ratio (6 -5 : 10) but does not regard the discrepancy from Cushny's 

 ratio (16 : 30) as having any significance. Biberfeld's original state- 

 ment [1908] that the racemic base is as active as the laevo-variety is 

 certainly erroneous. Schultz [1909, 2] states that the ratio of the 

 activities of dl- and 1-adrenaline on the frog's eye and the toxicity 

 ratio for white mice is the same as that of the pressor activities, 

 namely 1:15. 



Various authors have suggested that d-adrenaline renders the 

 organism less sensitive to the action of the natural 1-variety and to 

 some extent confers an " immunity," so that subsequent doses of 

 1-adrenaline have a much smaller effect than is normally the case. 

 This has been claimed for the pressor action by Frohlich [1909], for 

 the toxicity (to mice) by Abderhalden in collaboration with Slavu 

 [1909] and with Kautzsch [1909], and for the diabetic action by 

 Waterman [1909, 191 ij. With regard to the last-named effect Pollak 

 [1909, 1910] has, however, come to a different conclusion and considers 

 that d-adrenaline is as little able to prevent glycosuria by 1-adrenaline 

 as a previous dose of 1-adrenaline itself. A phenomenon, similar to 

 that observed by Frohlich, has recently been described by Ogawa 

 [1912] who finds that the secondary vaso-dilatation referred to 

 above (p. 99), when due to d-adrenaline, is not so readily abolished 

 by 1-adrenaline as the dilatation caused by (smaller doses of the more 

 active) 1-adrenaline. 



Physiological Methods of Estimating Adrenaline. 



At a time when little was known of the chemistry of adrenaline, 

 the methods employed in its estimation were perforce physiological, 

 and even now the best physiological methods are preferable to the 



