Selected monographs.

Date:: 1888

Catalogue details

Licence: Public Domain Mark

Credit: Selected monographs. Source: Wellcome Collection.

55/440 (page 39)

conditions in the fluid yielded by the capsules. We must continue to maintain the assumption, which is supported by other considerations, that the transudation which exudes from the glomerular vessels is feebly albuminous in its normal state, and this supposition furnishes us with a means whereby we may explain the presence of the minute proportion of albumen in normal urine, and the occurrence of physio- logical albuminuria, in a manner at once complete and satis- factory (see p. 22, et seq.). III. The Dependence op Albuminuria upon Alteeations in THE BlOOD-PeESSURE. Proceeding from the supposition, which we have shown to be perfectly tenable, that the normal fluid in the Bowman- Miiller's capsules is a transudation yielded by filtration, and as regards its constitution dependent upon the pressure of the blood, many experimenters have endeavoured to produce albuminuria by altering the general blood-pressure of the body, or the pressure in the vessels of the kidney. It is necessary that we should minutely discuss these attempts, on the one hand, because endeavours have been made to obtain conclusions therefrom as to the origin and secretion of the urine and the importance of the blood-pressure in the pro- cess, and secondly, because these experiments have been made to serve as a basis for the explanation of pathological processes. Unfortunately we find many difl&culties in form- ing conclusions as to their value for the above purposes, and these we shall presently endeavour to point out. The con- ditions are not sufficiently simple to justify the expectation that the discovery of albumen in the urine would enable us to decide as to how far its production had been influenced by any possible change of pressure in the renal circulation. For, although we are correct in supposing that the transuda- tion in the Bowman-Miiller's capsules is subject to the laws governing filtration-pressure, we are by no means to conclude that the urine as a whole is placed under the same rules. The urine is, as I have already explained, to be compared to a stream fed by two sources, which differ from each other as