214 INTERNAL SECRETION 



secretion at, and surrounding, the site of injection was rather 

 diminished than otherwise. 



The failure on the part of adrenalin to stimulate the secretory 

 activity of the sweat glands is undoubtedly a very remarkable 

 phenomenon, for it is quite certain that these glands are fur- 

 nished with a sympathetic innervation. 



Adrenalin stimulates the sweat glands of the frog to active 

 secretion. After the injection of small quantities of adrenalin into 

 the dorsal lymph space, the entire body of the animal becomes 

 covered with secretion. If the secretory process in the glands of 

 the nictitating membrane is observed under the microscope 

 (Strieker and Spina), it will be seen that the introduction of 

 adrenalin is followed by progressive enlargement of the glandular 

 epithelium and by the extrusion of drops of secretion, in exactly 

 the same manner as after stimulation of the sympathetic nerves 

 (Drasch). 



S. Lieben found that adrenalin produced marked contraction 

 of the pigment cells of the skin of frogs, a dark-coloured frog 

 becoming light in the space of ten minutes. This effect of 

 adrenalin upon the pigment cells is not brought about by the local 

 anaemia, nor is it a reflex effect ; it is the result of the direct 

 action of the substance. According to Gaup, the pigment cells 

 are controlled by the sympathetic. 



Adrenalin exercises a similar agglomerating effect upon the 

 pigment granules in the pigment epithelium of the retina of frogs, 

 but this is seen only after local application. This agglomerating 

 action may even, to a certain extent, inhibit the migration of the 

 pigment in response to the stimulus of light, and where this for- 

 ward movement has already taken place, a further agglomeration 

 of the pigment granules will be produced in a varying degree by 

 the action of adrenalin (Klett). 



Among the physiological effects of adrenalin, those must be 

 included which this substance produces in the composition of the 

 blood. According to Foa, adrenalin reduces the alkalinity and 

 produces acidity of the blood. Falta and Berterelli found that the 

 injection of adrenalin is followed by an increase in the specific 

 gravity ; by hyperglobulia with isolated erythroblasts ; and by 

 marked leucocytosis affecting the neutrophile polynuclear cells, the 

 eosinophile cells being very much reduced. In dogs with 

 hypereosinophilia of about 12 per cent., the injection of adren- 

 alin is followed by a reduction to .3 per cent. Eppinger and Hess 

 discovered that the physiological eosinophilia of rabbits is reduced 

 by the action of adrenalin. The morphological structure of the 

 blood is influenced by adrenalin in a manner the reverse of that 

 of pilocarpin which, it is well known, produces lymphocytosis and 

 eosinophilia in both man and rabbits (Neusser). 



Metabolism. The influence which adrenalin exercises upon 

 metabolism demands special consideration. The investigations of 



