﻿pharmacologicaij actiox of uranium 



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of hydrocyanic acicF. I Unci its stnnulating effect upon the respira- 

 tion to be ranch smaller than that of the cyanides. Early in its 

 action the depression of the respiratory center becomes evident. 

 After a time the respiration ceases, but the circulation remains in 

 g^ood condition and if artificial respiration be given the animal 

 may be kept alive for a long time. Normal respiration does not 

 return until after ten to thirty minutes, if it is reinstated at all. 

 The cessation of the breathing is usually rather rapid and there is 

 but little tendency toward Che;sTie- Stokes respiration, as is often 

 seen with the cyanides. I have repeatedly noticed when the res- 

 piration had become greatly depressed that the injection of another 

 dose of the substance would tend to re^dve the animal, apparently 

 ver\^ much in the same way as the cyanides. This is probably due 

 mainly to a slight direct stimulation of the central nervous system, 

 for the effect comes on immediately after injection of the drug. 

 The remarkable specific depression which this substance exercises 

 on the respiratory center reminds one of morphine. I have regu- 

 larly observed that, after a certain amount of the drug had been 

 administered, the animal would pass into a sort of comatose condi- 

 tion, in which but little ether would be required to maintain the 

 anaesthesia'. This may ])e due to the gradually progressing central 

 paralysis, but it may also be contributed to, in part at least, by 

 some speciiic action on the blood. The view has been generally held 

 of late years that uranium retards the reduction of the oxyh^emo- 

 globin in the tissues. I shall refer to this point again. 



Action on the Blood. Uranium and the cyanides both prevent 

 coagulation when added in sufficient quantity to drawn blood. Is 

 this action the same in each case ? I have attempted to throw 

 some light on this cjuestion by trying the action of the drugs on 

 certain common ferments. 



If an aqueous extract of potato peelings be treated with a small 

 amount of tincture of guaiac. an oxidizing ferment from the potato 

 will at once oxidize the guaiac over to a blue compound. If a 

 uranium solution (either the acetate, nitrate, or double salt) be 

 added to the aqueous extract before the tincture of guaiac is poured 

 in, there ^^'ill be no hindrance whatever to the normal change over 

 to the blue compound. Apparently uranium exercises no inhibitory 

 power at all upon this ferment. If a solution of potassium cyanide 



s Kobert, Ueher Ciianhict'naemoglo'bin mnl dcy Xachweis der BlavsU arc . Srntt- 

 gart, 1891. {Lchrliuch der lufoxicaiiouen, 2ci ed.. pp. 94-99.) 

 Geppert, Zeiisclirift fin- 'kUnisclie Medicin, XV, 208, 307. 

 ^ Meltzer, Amevican Journal of Physiology, XXIII, (1909), 141. 



