The content of sugar in the blood under common laboratory conditions / by Ernest Lyman Scott.

  • Scott, E. L. (Ernest Lyman), 1877-1966.
Date:
[1914]
Catalogue details

Licence: Public Domain Mark

Credit: The content of sugar in the blood under common laboratory conditions / by Ernest Lyman Scott. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

    19/50 (page 285)
    what has been said, it will be seen that those experiments in the past in which the blood has been drawn from an artery or vein without anesthetics have a very doubtful value, since it is hardly probable that an animal will undergo such an operation and remain in perfect tranquillity. The necessary restraint is of itself suffi- cient to influence the results as indicated by animals number 108 and no. Of the disturbing effect of anesthetics more will be said later. There remains then only the possibility of rapidly killing the animal with the least possible excitement and the rapid with- drawal of the sample of blood after death. This was long ago appreciated by Pavy, who killed his animals by pithing with a Bernard needle and then collected the blood from the heart or from the thoracic cavity after severing the large blood vessels. Sudden decapitation and collection of the blood from the severed neck vessels seemed to offer some advantages over Pavy's method, and was used throughout the present work. The interval during which the animal was held' before decapitation seldom exceeded three seconds, while about fifteen to twenty seconds more were required for the collection of the blood. As a further precaution against excitement, an attendant, from whom the animals were accustomed to receive food, brought them to the laboratory and assisted throughout the preparation of the animal and the collec- tion of the blood. That the amount of blood drawn relative to the total amount in the body may affect the concentration of sugar in the sample seems to have been overlooked by previous investigators. In studying this relationship a number of standard experiments were tabulated in the order of the increasing amounts of blood drawn, when this was expressed in grams per kilo of body weight. It was then found that the respective concentrations of sugar were arranged in the reverse order: that is, the more blood drawn per kilo of body weight, the lower is its concentration of sugar. This is wholly independent of the actual amount of blood drawn, as is shown below. The phenomenon is somewhat surprising since we know that hemorrhage under certain conditions causes hyperglycaemia. The relationship of which we are speaking, however, is not to be confused with the so-called hemorrhage hyperglycaemia as that term is commonly used.