THE TRUE BLOOD SUGAR LEVEL IN INSULIN
SHOCK AND CONVULSIONS
BY LOUIS B. DOTTI AND M. CAROLINE HRUBETZ
(From the Department of Physiology, College of Physicians and Surgeons,
Columbia University, New York)
(Received for publication, October 30, 1935)
In previous work done on the blood sugar level of insulinized
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animals, attempts have been made to determine the blood sugar
level during convulsions. The results have been very inconsistent
until Dotti (l), working with rabbits, found that at the incidence
of convulsions the true blood sugar level is zero.
Since the rat manifests all stages of insulin reaction ranging
from simple weakness to convulsions, it was thought worth while
to determine the true blood sugar level of rats at the incidence of
convulsions as well as during the time of marked prostration which
precedes the onset of the convulsions. The rabbit exhibits a
short period of prostration with sudden onset of convulsions,
while the rat passes through a prolonged period of weakness be-
fore convulsions become manifest. In the rabbit this period of
weakness lasts but a few minutes, while in the rat it may last for
an hour or more.
All experiments were performed upon rats which had been
fasted for 24 hours. 10 units of Lilly’s insulin were injected per
kilo, subcutaneously, and at the appropriate time, as indicated
by the symptoms, the animals were killed by decapitation. The
blood was collected in a small porcelain dish which had been
dusted with powdered sodium citrate.
The blood proteins were precipitated by the method of Folin
and Wu (2), and the reducing substances in the filtrate were de-
termined by the Shaffer-Hartmann method (3). The conversion
table of Duggan and Scott (4) was used for determining the reduc-
ing substance of the sample in terms of glucose. The fermentable
fraction was removed by the yeast method of Somogyi (5). The
141
142 Blood Sugar Level in Insulin Shock
same precautions were taken with the yeast cells as were described
in a previous paper (1). The results obtained are shown in
Table I.
Dotti (6) has followed the blood sugar level of rabbits for 6
hours after 2 units of insulin per kilo. He found that the total
blood sugar dropped progressively until the onset of convulsions.
When convulsions did not occur, the blood sugar fell to a mini-
mum value of about 50 mg. of total sugar, after which there was a
recovery with a rising sugar level. Hrubetz (7), using subcon-
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TABLE I
Reducing -. Power of Blood during Shock and at Convulsions
Mean value ML%Xl Mean devirt-
deviation tion of mean
_- --
Controls (50 observations) mg. per 100 cc. mg.per 100 CC. mg. per 10 0 cc.
Total reducing substance.. . . . . . 114 12.0 1.7
Non-fermentable reducing sub-
stance.. . . . . . . . . . . . . . . . . . . . . . 43 4.4 0.6
Fermentable reducing substance
(by difference). . . . . . . . . . . . . . . 71 11.0 1.6
Rats in shock (62 observations)
Total reducing substance.. . . . . . 54 6.6 0.8
Non-fermentable reducing sub-
stance.. . . . . . . . . . . . . . . . . . . . . 38 6.6 0.8
Fermentable reducing substance
(by difference). . . . . . . . . . . . . . . 16 7.0 0.9
Rats in convulsions (53 observa-
tions)
Total reducing substance.. . . . . . 42 5.0 0.7
Non-fermentable reducing sub-
stance.. . . . , . . . . . . . . . . . . . . . . . . 40 5.0 0.7
vulsive doseson rats, showed a progressive fall in the total reduc-
ing power through the 1st hour after injection, after which there
was a return to the normal level. Dotti (1) has shown with
rabbits that the non-fermentable fraction of the blood sugar does
not change, at least not significantly, after insulin. The material
presented in this paper shows that this is also true for rats. From
these results it seems, therefore, that during the course of insulin
shock, there is a progressive fall in the true blood sugar level
through the period of prostration to the incidence of convulsions
when this level is zero.
L. B. Dotti and M. C. Hrubetx 143
BIBLIOGRAPHY
1. Dotti, L. B., J. Biol. Chem., 104, 535 (1934).
2. Folin, O., and Wu, H., J. Biol. Chem., 38, 81 (1919).
3. Shaffer, P. A., and Hartmann, A. F., J. Biol. Chem., 46, 365 (1920-21).
4. Duggan, W. F., and Scott, E. L., J. Biol. Chem., 67, 287 (1926).
5. Somogyi, M., J. BioZ. Chem., 78, 117 (1928).
6. Dotti, L. B., Am. J. Physiol., in press.
7. Hrubetz, M. C., Am. J. Physiol., 110, 384 (1934).
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