Researches on the nature of the normal destruction of sugar in the animal system / by Frederick William Pavy.

  • Pavy, F. W. (Frederick William), 1829-1911.
Date:
[1855]
Catalogue details

Licence: Public Domain Mark

Credit: Researches on the nature of the normal destruction of sugar in the animal system / by Frederick William Pavy. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    dogs and rabbits, I am able to affirm, what has been also ob- served in Paris, that whilst the blood contained in the right cavities of the heart is largely impregnated with sugar, that which is circulating in the arterial .system or derived from the left ventricle, is almost destitute of this principle. From this it is evident, that a great portion of the sugar has undergone destruction during the transit of the blood through the pul- monary organs. The difference of reaction communicated by the blood removed from the right and left side of the heart is always exceedingly striking and well marked; the one, after its colouring and albuminous constituents have been separated, giving an exceedingly abundant orange-yellow precipitate on ebulhtion with the copper test,^ (Barreswil's solution); the other, similarly treated, merely a very small amount of yellowish precipitate, just sufficient to create a turbidity, which will vary slightly in intensity according to the period that has elapsed since the ingestion of food. Although the sugar disappears to such an extent during the circulation of the blood through the capillaries of the. res- piratory organs, yet, after very numerous analyses, I may state, ' I may here briefly slate the method that has been employed in searching for the presence of sugar in the animal solids and fluids. If it be a fluid, as for instance blood, that is to be examined, it is simply mixed with nearly an equal bulk of the pounded crystals of sulphate of soda, and exposed to the temperature of ebullition. The whole of the colouring and albuminous constituents are by these means precipi- tated, and a perfectly clear fluid runs through the filter, in which the slightest trace of sugar is easily recognised, by the aid of Barreswil's copper solution. With a solid, it is requisite that it should be cut into small pieces, and intimately pounded in a mortar with the sulphate of soda; the application of heat separates a limpid and transparent fluid, which may be obtained by filtration. The sulphate of soda, with which this clear fluid is saturated, does not at all interfere with the action of the test, that is subsequently employed. For the composition of the blue liquid of Barreswil (vide ' Guy's Hospital Reports,' Oct., 1853, p. 322). It is the test now always employed by Bernard in his experiments; and I may say, with regard to its action for the detection of the presence of sugar in blood and the animal solids, that I have now made several hundred analyses of these substances, and the uni- form results that I have obtained induce me to speak in the strongest terms of confidence, respecting the accuracy and delicacy of this reagent. In the exami- nation of specimens of urine, where there are only traces of sugar present, I am well aware that it does not react with the same facility; but in this case, there would seem to be certain saline ingredients also present, which have the effect of impeding its operation.