INTRA VENOUS INJECTION OF SUPRARENAL EXTRACT. 95 1 



showed itself in very slow and languid movements. This may, however, 

 be due to the veratrine-like effect which the extract produces upon 

 muscular tissue (see below). The subject has been worked at more 

 recently in my laboratory by Swale Vincent. 1 who has performed 

 a large number of experiments upon various animals, and has not only 

 confirmed most of our results, but has added several other facts. 

 Vincent commonly obtained fatal results in guinea-pigs with doses of 

 6 grms. of fresh gland. In rabbits he found the results to be inconstant. 

 The hind-limbs become paralysed before the fore-limbs in all animals 

 investigated. Doses insufficient to cause a fatal result produce im- 

 munity to larger doses which would otherwise be fatal, and this effect may 

 last a few weeks. The action is produced by the medulla of the gland 

 only ; extracts of a large number of other organs and tissues were tried, 

 but none produced any effect when injected hypoclermically (Vincent). 



Intravenous injection. The intravenous injection of suprarenal 

 extract produces a powerful physiological action upon the muscular 

 system in general, but especially upon the muscular walls of the blood 

 vessels, and the muscular wall of the heart. A certain amount of action 

 is also manifested 

 upon some of the 

 nerve centres in 

 the bulb, especi- 

 ally the cardio- 

 inhibitory centre, 

 and to a less 

 extent upon the 

 respirator y 

 centre. 2 



Action on 

 skeletal muscle. 

 The effect upon 

 the skeletal 

 muscles is well 

 shown in the frog 

 (Fig. 8 7), and can 

 also be seen in 

 mammals. The 



o FIG. 87. Effect of suprarenal extract upon muscle contraction in 

 the frog. A, Normal muscle curve of gastrocnemius ; B, Curve 

 during suprarenal poisoning, but otherwise under the same 



taken 

 conditions as A. 



Time tracing, 100 per sec. 3 



contraction of the muscle in response to a single excitation of its nerve 



1 Journ. Physiol., Cambridge and London, 1897, vol. xxii. p. 111. 



2 Oliver and Schafer, " Proc. Physiol. Soc.," March 1894 (Journ. Physiol., Cambridge 

 and London, vol. xvi.) ; "Proc. Physiol. Soc.," March 1895 (ibid., vol. xvii.). These 

 were preliminary communications. The detailed account of the experiments is to be found 

 in the Journ. Physiol., Cambridge and London, vol. xviii. pp. 230-276. The chemical 

 work in connection with our experiments was carried out by Moore ; his papers on the 

 subject will be found referred to by Halliburton, on pp. 90-92. Since the first com- 

 munication to the Physiological Society there have appeared a large number of papers 

 on the subject, for the most part confirming the results there announced. The follow- 

 ing are some of these Szymonowicz, Anz. d. Akad. d. Wiss. in Krakau, February 

 1895; Arch. f. d. ges. Physiol., Bonn, 1896, Bd. Ixiv. S. 97; Cybulski, Gaz. lek., 

 Warszawa, and Anz. d. Akad. d. Wiss. in Krakau, 1895, reported in Centralbl. f. Physiol., 

 Leipzig u. Wien, 1895, S. 172 ; Velich, Wien. mcd. BL, 1896 ; Biedl, Anz. d. k. k. Ges. d. 

 Aerzte, in Wien, 1896, &nd Arch. f. d. ges. Physiol., Bonn, 1897, Bd. Ixvii. ; Gottlieb, Arch. 

 /. expcr. Path. u. PharmakoL, Leipzig, 1896, S. 99; Ocaiia. Ad. d. I. soc. cxp. d. Hist. 

 Nat., Madrid, 1897. 



3 Figs. 87, 88, 89, 90, and 91 are taken from the Journ. Physiol., Cambridge and 

 London, 1895, vol. xviii. No. 3. 



