134 REPORT— 1887. 



insusceptibility of rabbits to the influence of atropine. Under the influence 

 of one grain of atropine, and even of half a grain, cats are markedly ex- 

 cited, are unable to take food, and exhibit evidences of serious disturbance. 

 Rabbits show no such symptoms. Even a dose of 4 grains of atropine 

 seemed to have little disturbing effect, but with that dose results as 

 regards the urine indicating an approach to those of the cat were 

 obtained. 



As regards the appearance of albumen, in the majority of instances 

 traces of albumen were obtained some time after the injection of atropine; 

 in a few, quite distinct evidence of its presence in very small amount 

 The evidence was usually most distinct at the time when the total urine 

 was rising and the total N. falling. But regarding albumen, no results 

 were obtained definite enough to allow of any conclusions being drawn as 

 to its relation to the separation of nitrogen. 



In cats on whom several experiments had been made there seemed to 

 be some degree of tolerance of the drug ; but though a few experiments 

 Avere tried directly in relation to albumen they yielded nothing definite. 

 The Committee next considered whether a method could be adopted which 

 would admit of microscopic examination of kidneys of animals submitted 

 to the influence of atropine. 



For this purpose a number of rabbits were injected with a solution of 

 indigo-carmine, after the method of Heidenhain. The rabbits were first 

 of all injected with atropine in varying doses and at varying intervals; 

 after its administration the indigo-carmine was injected. It was thought 

 that if any marked influence were exerted on the renal epithelium, it might 

 be indicated by variations in the extent to which the colouring matter 

 was picked up by the cells. Though the injections were satisfactorily 

 enough accomplished, the experiments yielded no information beyond 

 what might have been expected from Heidenhain's description of what 

 normally occurs. It may be, however, that the insusceptibility of rabbits 

 to the influence of atropine renders them unsuitable subjects for such an 

 experiment. Tlie Committee think it probable that this method might 

 yield some results with cats or other animals, and a further set of trials 

 in this direction may yet be conducted by one of the members. 



Your Committee think that what evidence has been obtained strongly 

 supports the view that the mechanism for the separation of the watery 

 constituents of the urine is different from that for the separation of the 

 specific constituents. The effects of atropine which the experiments 

 demonstrate could be explained by a stimulating action on the renal 

 epithelium, followed by a paralysis or state of exhaustion. This, at least, 

 would account for the great increase in the elimination of N., followed 

 by a decrease. It would also account for the diminution of water, 

 followed by an increase, if the cells were supposed to possess the function 

 of absorbing water to any extent. The meagre results relating to albu- 

 men do not justify the offering of any suggestion regarding its ap- 

 pearance. 



Tour Committee think that a continuation of the experiments on the 

 lines of some of the methods indicated, as well as on others, might elicit 

 further facts of value. One of their number hopes to be able himself to 

 pursue the subject further, and if he obtains any results to communicate 

 them to some future meeting of this Association. In view of this the 

 Committee respectfully suggest they might now be discharged. 



