INFLUENCE OF DUCTLESS GLANDS ON METABOLISM. 



particular extirpation is toxic, especially for other animals which have 

 been submitted to the operation. But it is probable that the blood 

 of an animal dying slowly as the result of any disease, would be to 

 some extent toxic, and the toxic principles would more powerfully affect 

 animals whose resisting power had been lessened by a recent severe 

 operation. However this may be, whether the suprarenal capsules do 

 or do not destroy a toxic principle which is formed elsewhere, and which 

 would otherwise accumulate in the blood, they unquestionably produce 

 a material which has entirely different properties from those stated to 

 be possessed by the blood of animals deprived of their capsules. This 

 material, which is probably the basis of the internal secretion of the 

 glands, has most active physiological properties. 



Hypodermic injection of extracts General effects. The action 

 upon normal animals of extracts of suprarenal was first inves- 

 tigated by Pellacani and Foa, 1 both alone and in conjunction. They 

 injected subcutaneously extracts of the glands, made with water, and 

 observed the symptoms which resulted. They found that animals 

 (dogs) were killed by subcutaneous injection of extract of calf suprarenal. 

 Their results were criticised by Alexander, 2 w T ho pointed out that 

 there was liability to chemical change in their preparations, and were 

 not confirmed by other observers, but they are, nevertheless, in the 

 main correct. 



In conjunction with G. Oliver, 3 I have myself made a number of 

 observations upon the effect of subcutaneous injection of water and 

 glycerin extracts of suprarenal. We found that the animals were 

 usually unaffected by moderate doses, but witli larger doses showed 

 quickening and augmentation of the heart-beat, shallow and fast 

 respirations, and fall of temperature. Guinea-pigs, we found, would 

 stand a large subcutaneous dose of suprarenal extract without 

 showing any symptoms at all, or with only a slight acceleration 

 and increase of the force of the pulse. The same appeared to be 

 the case with the cat and with the dog, unless a very large dose 

 were injected, when the symptoms above enumerated became very 

 marked. Rabbits, on the other hand, were more susceptible to the 

 influence of suprarenal extracts. If a large dose w r ere given, the animal 

 succumbed within half an hour. If, on the other hand, the dose was 

 only moderate in quantity, it did not show any symptoms at all for 

 some hours, but then it might suddenly succumb. This primary absence 

 of symptoms was also noted by Foa and Pellacani in dogs. They state 

 that in many of the animals which they experimented upon in this way, 

 there were no symptoms at all apparent upon the day upon which the 

 injection was given, but that the next morning the animal was usually 

 found dead. The cause of death, it may be added, is not by any 

 means clear. Foa and Pellacani have supposed that it may be due to 

 paralysis of the respiratory centre, but the slight effect which intra- 

 venous injection of suprarenal extract produces upon this centre does 

 not lend support to this conjecture. 



In frogs we found the effect of the water extract or decoction injected 

 into the dorsal lymph sac was to produce a temporary paralysis, which 



1 Arch, per U sc. mcd., Torino, 1879, 1880, tomes iii., iv., and vii. ; Arch. Hal. de 

 biol., Turin, 1888, p. 56. 



2 Beitr. z. path. anat. u. z. ally. Path., Jena, 1892, Bd. xi. 



3 Journ. Physiol., Cambridge and London, 1895, vol. xviii. p. 235. 



