56 PHYSIOLOGY CHAP. 



of intoxication, and even death, if the frog is not very large. The 

 dose of 1 mgrm. is always fatal to the decapsulated frog, while it 

 takes 4 mgrms. to kill one that is normal. On the other hand, the 

 brothers Marino-Zuco state that either the excision of one capsule 

 alone, or the injection of non-toxic doses of neurine will after 

 fourteen to twenty-four days cause slate-grey spots to appear on 

 the skin, the buccal mucosa, and the under surface of the tongue. 



These experimental data are the basis of the theory sustained 

 by Marino-Zuco and Albanese, viz. that Addison's disease and the 

 effects of artificial destruction of the capsule are due to neurine 

 intoxication, and that the function of the capsules consists in 

 modifying the neurine produced by the body, so as to render it 

 innocuous. 



In order to explain the process by which the capsules neutralise 

 the activity of neurine, Carbone (1894) carried out a series of 

 experiments to determine its effects upon normal and decapsulated 

 dogs, tested by its elimination in the urine. He found that the 

 normal dog bears a hypodermic injection of small doses of neurine 

 without any symptoms ; in the decapsulated dog, on the contrary, 

 the same dose immediately produces salivation, and after a few 

 hours, vomiting, diarrhoeal discharges, paralysis of the hind limbs. 

 This led him to suspect that in the normal dog the neurine was 

 rapidly destroyed or fixed by the capsule, while in the decapsulated 

 animal it circulated and was eliminated unchanged in the urine. 

 In order to verify this surmise, Carbone estimated the neurine 

 eliminated by the urine, and found that the amount did not vary 

 perceptibly in the normal dog and in those which had suffered 

 ablation of three-fourths of both capsules. In both cases, only a 

 small part, at most a fourth, of the injected neurine passes into 

 the urine. The remainder is probably transformed or retained in 

 the body. 



In regard to the theory that the toxins causing the cachexia 

 of Addison's disease consist in neurine or glycerophosphate of 

 neurine, Neumeister points out that the neurine and glycero- 

 phosphoric acid found in the capsules may come from decom- 

 position of their lecithin or choline, owing to manipulation of the 

 chemical extracts. On the other hand, Oliver and Schafer (1895) 

 showed that the effects of injecting phosphate and glycero- 

 phosphate of neurine are totally different from those produced by 

 suprarenal extract in toto. 



Taken as a whole, these data leave no doubt as to the protective, 

 antitoxic action of the suprarenal capsules, but it is still uncertain 

 if this is effected by the removal from the blood of specific toxic 

 substances, or by the secretion and output into the blood and 

 lymph of one or more active substances, which are directly or 

 indirectly antitoxic. 



According to a theory brought forward by Cybulski (1895), the 



