14 SUPBAKENAL GLANDS. 



Besides this action on the sympathetic nerve terminals there is 

 some action on the heart itself. a 



ACTION ON THE EYE. 



The action on the small blood vessels is well shown by dropping 

 a dilute solution into the conjunctival sac of an animal, when the 

 conjunctiva becomes pale and bloodless and the pupil dilates. 6 

 This action on the conjunctiva occurs even after the use of solutions 

 as dilute as 1-120,000. The action on the pupil of the excised frog 

 eye has been advocated by Ehrmann c as a method for determining 

 the amount of active principle present in unknown solutions, but 

 the objection to this method is the difficulty in exactly measuring the 

 size of the pupil and the uncertainty as to absorption through 

 the eye membranes. In Ehrmann's hands, 0.000025 mg. could be 

 thus determined with certainty, although 0.0000001 gram produced 

 a distinct dilatation, while 0.00000005 gram was inactive. Cameron's 

 results with this method were unsatisfactory. 



ACTION ON ANIMALS. 



A second method of showing this vaso-constrictor action is by per- 

 fusion of the blood vessels in frogs. Lawen d has obtained a response 

 showing a decided constriction of the vessels with 0.2 per million 

 adrenalin, but the method is tedious and frogs vary much in their 

 response. Cameron obtained a feeble reaction with 0.1 per million. 

 Details of this method may be found in English in Cameron's paper. 

 Meyer 6 placed sections of the beef subclavian arteries in Ringer's 

 solution with the addition of adrenalin. He found that most of them 

 responded with under 1-100,000,000, but not all. With increasing 

 amounts of adrenalin the contraction was greater — usually 1-50,000 



a Gottlieb, P. Ueber d. Wirkung d. Nebennierenextracte auf Herz u. Blutdrack. 



Arch. f. Exp. Path., vol. 38, p. 99, 1897. 

 b Meltzer, S. J., and Auer, K. M. Ueber d. Einfluss d. Nebennierenextraktes auf d. 

 Pupille d. Frosches. Cent. f. Physiol., vol. 18, p. 317, 1904. 

 Kahn, R. H. Ueber d. Beeinflussung d. Augendruckes durch Extrakte chromarn- 



nen Gewebes (Adrenalin). Zent. f. Physiol., vol. 20, p. 33, 1906. 



Lewandowsky, M. Ueber d. Wirk. d. Nebennierenextractes auf d. glat. Muskeln, 



im besond. des Auges. Arch. f. Anat. u. Phys., Physiol. Abtheil., 1899, p. 360. 



c Ehrmann, R. Ueber eine physiol. Werthbestimmung des Adrenalins. Arch. f. 



Exper. Path. u. Pharmakol., vol. 53, p. 97, 1905. 



Zur Physiol, u. experiment. Path, der Adrenalinsekretion. Arch. f. Exp. 



Path. u. Pharmakol., vol. 55, p. 39, 1906. 

 Ueber die Wirkung des Adrenalins auf die Hautdriisensekretion des Frosches. 

 Arch. f. Exp. Path. u. Pharmakol., vol. 53, p. 137, 1905. 

 d Lawen, A. Quantitative Untersuchungen iiber d. Gefasswirkung von Suprarenin. 



Arch. f. Exp. Path. u. Pharmakol., vol. 51, p. 422, 1904. 

 « Meyer, O. B. Ueber einige Eigenschaft. d. Gefassmuskulatur. Zeits. f . Biol., vol. 

 48, p. 365, 1906. 



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