338 PHYSIOLOGY: KLEINER AND MELTZER
so constant as it has been assumed to be, but that it is affected by a
number of conditions, and that at least some of these may not affect
length and spread in the same manner. Attention has been called to
these facts because they have not been given adequate consideration in
genetic research on the behavior of flower size in Nicotiana and other
The experiments reported upon above have, in part, been made possi-
ble by an allotment from that portion of the Adams Fund of the United
States Department of Agriculture granted to the Agricultural Experi-
ment Station of the University of California.
'Setchell, Studies in Nicotiana, I, Univ. of Cal. Pub. Bot., 6, 8,1912.
2 Ibid., p. 29.
RETENTION IN THE CIRCULATION OF DEXTROSE IN NOR-
MAL AND DEPANCREATIZED ANIMALS, AND THE EFFECT
OF AN INTRAVENOUS INJECTION OF AN EMULSION OF
PANCREAS UPON THIS RETENTION
By I. S. Kleiner and S. J. Meltzer
DEPARTMENT OF PHYSIOLOCY AND PHARMACOLOGY, ROCKEFELLER INSTITUTE
FOR MEDICAL RESEARCH
Read before the Academy. April 19, 1915. Recived, April29, 1915
The content of dextrose in the circulating blood of normal animals
is almost constant, it amounts to about 0.1 percent. The carbohy-
drates of the foodstuffs form the main source of dextrose in the body.
On their way from the digestive tract the carbohydrates are transformed
into various forms of saccharides; but all are finally converted largely
into glycogen, which is stored up mostly in the liver. The blood obtains
its supply of dextrose from the glycogen of the liver, and distributes
it among the tissues of the body according to their demand for it. In
the normal animal none of the dextrose escapes through the kidneys.
Accordingly the constancy of the amount of dextrose in the blood is
regulated by a mechanism which controls either of the two factors;
the supply of or the demand for it.
In diabetes the dextrose content of the blood is higher than normal,
is variable in amount, and, when it is sufficiently high, dextrose escapes
through the kidneys. The cause of the increase of the blood dextrose,
or hyperglycaemia, may be found either in a decrease in the demand of
the tissues for dextrose, that is, the tissues burn dextrose less readily
than in normal conditions; or in an increase in the supply, that is, the
liver supplies the blood with more dextrose than in normal conditions.