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ACETONE BODIES. 821
the body fat is consumed, and in several cases a certain relation has
been found between the fat consumed and the acetone bodies eliminated.
Certain investigators (Geelmuyden, Schwarz, Waldvogel) have
also observed an increase in the acetonuria on partaking of fatty food,
and Forssner l
has indeed found a certain parallelism lei ween the
acetone elimination and the fat taken up. For the present the fats are
considered as the most important source of the acetone bodies.
The three acetone bodies occurring in the urine, as above stated, are
acetone, acetoacetic acid and /3-oxybutyric acid, and this last is considered
as the mother-substance of the other two. If /3-oxybutyric acid,
CH3.CHOH.CH2.COOH, is introduced into the animal body, it is burnt
if the quantity is not too great, while if in excess it passes into the urine
as acetoacetic acid, CH3.CO.CH2COOH. This acid can also be burnt,
but if large quantities are introduced it appears in part in the urine and
readily splits into acetone, CH3.CO.CH3, and CO2. Acetone is in part
burnt in the animal body, but a part is eliminated by the kidneys and
especially by the lungs. We can imagine that the /3-oxybutyric acid is
a physiological metabolic product which normally is completely changed
into acetoacetic acid and acetone, and in diabetes and especially with
lack of carbohydrates is formed to an increased extent, or its combustion
made more difficult, so that in the first place acetone and acetoacetic
acid pass into the urine and in severe cases also /3-oxybutyric acid (acidosis).
In this connection it must be borne in mind that, because of the previously-
mentioned (page 774) reversibility of the process, the direction may also
be reversed, that is acetoacetic acid can also be changed into /3-oxybutyric
acid in the animal body and this has been proven by perfusion of livers
(Friedmann and Maase) as well as in animals (Dakin) and in diabetics
(O. Neubauer)2
.
Since leucine in perfusion experiments with livers yields acetoacetic acid
(Embden and Engel) and also, as Baer and Blum 3
found, that leucine and iso-
valeric acid increased the /3-oxybutyric acid elimination in diabetics, it has been
accepted that a formation of /3-oxybutyric acid takes place from the leucine
with isovaleric acid as an intermediary product
:
(leucine CH3) 2CH.CH2 .CH(XH2 ).Co6h->(CH3 ) 2 CH.CH2.COOH, isovaleric acid).
Valine (a-amino-valeric acid (CH3)2CH.CH(NH2 ).COOH) is, on the contrary,
not an acetone former.
1
Magnus-Levy, Arch. f. exp. Path. u. Pharm., 42; Geelmuyden, 1. 0., and Norsk,
Magasin for Laegevidenskaben, 1900; see also Zeitschr. f. physiol. Chem., 41; Schwarz,
Deutsch. Arch. f. klin. Med., 1903; Waldvogel, Centralbl. f. inn. Med., 20; Forssner,
jskand. Arch. f. Physiol., 22 and 23.
2
Friedmann and Maase, Bioch. Zeitschr., 27; Dakin, Journ. of biol. Chem., 8;
Neubauer, Maly’s Jahresb., 40, 849.
3
Arch. f. exp. Path. u. Pharm., 55 and 56; Embden and Engel, Hofme.ster’s
Beitrage, 11.
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