PHYSIOLOGY: KLEINER AND MELTZER 
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Both possibilities have groups of followers who have brought forward 
numerous experiments in support of either of the respective theories. 
It was experimentally estabhshed years ago that the complete removal 
of the pancreas brings on a severe hyperglycaemia, leading to consid- 
erable glycosuria and to the death of the animal. Here we are con- 
fronted again with the question, whether the presence of the pancreas 
in the normal animal favors the burning of the dextrose by the tissues, 
or whether it restricts the supply of dextrose to the blood by the liver. 
But there also arose another question, namely, whether the effect of 
the removal of that gland was due to a removal of a controlling sub- 
stance, or, whether it was due, in consequence of the operation, to an 
interference with the nervous mechanism which controls the supply of 
the dextrose. In case of the first alternative, namely, that the resulting 
hyperglycaemia is due to a removal of some substance, normally secreted 
by the pancreas, we have to assume that that substance belongs to that 
group of substances which are provided by glandular and other tissues 
for the proper maintenance of functions of the animal body, i.e., internal 
secretions, since a complete suppression of the external secretions of the 
pancreas never leads to hyperglycaemia or diabetes. 
We wish to report briefly results of several series of experiments which 
are likely to shed some light upon these questions. Most of our experi- 
mental series have one feature in common, namely, that the blood was 
provided with dextrose directly and not by way of the liver. In one 
series of experiments large quantities of dextrose (20 cc. of a 20% solu- 
tion of dextrose per kilo body weight) were injected intravenously into 
normal dogs. It was found by us, as it was found by some investigators 
before us, that the injected large surplus of dextrose disappeared quite 
rapidly from the circulation. Ninety minutes after the infusion, the 
dextrose content of the blood reached nearly the same level which it had 
before the injection. About one-half of the injected quantity of dextrose 
left the circulation through the kidneys; the other half went into the 
tissues. In nephrectomized animals also the dextrose returned to the 
previous level in the same length of time. Here we have a striking exam- 
ple of the ability and readiness of the circulation of a normal animal to 
rid itself of a large surplus of dextrose. 
In another series of experiments similar injections of dextrose were 
made into animals, the pancreas of which was removed by an operation 
a day or two before the dextrose infusion. The sample of blood taken 
from the animal before the intravenous injection of dextrose was strongly 
hyperglycaemic. It was then found that in these experiments the dex- 
trose content of the sample of blood, which was taken ninety minutes after 
