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PLACENTA. 64L
a considerable rise in the oxidation. For this reason Loeb believes that
the spermatozoa save fche life of the egg by bringing membrane forming
substances to the egg, but also other substances, which remove or make
inert a harmful substance or condition complex of the unfertilized egg,
so that even now the increased oxidation cannot have any harmful effect.
1
The enzymes of the sea-urchin suffer an increase in natural as well
as in artificial fertilization as Jacoby 2
has shown that glycyltryptophane
is split after fertilization but not before.
The placenta has recently been the subject of several investigations.
This tissue contains a protein which coagulates at 60-65° C. (Bottazzi
and Delfino) whose relation to the nucleoprotein, found by others, is
not clear. The protein found by Savare contained 0.45 per cent phos-
phorus. The nucleic acid studied by Kikkoji,3
which is very similar to
the thymus nucleic acid, originates from this nucleoprotein. Glycogen
occurs regularly in the placenta, and Moscati believes the human pla-
centa contains 5 p. m. glycogen. After removal the glycogen diminishes,
and after 24 hours it has disappeared. According to Lochhead and
Cramer 4 the quantity of glycogen in the placenta is not increased by
food rich in carbohydrate. In the fcetus (rabbits) the above authors
found that the placenta is a storage organ for glycogen until the second
half of the gestation period, when the liver begins to functionate in this
direction. From this time on the quantity of glycogen in the placenta
diminishes.
Enzymes of various kinds, proteolytic as well as lipolytic (mono-
butyrase), amylases and oxidases have been found in the placenta. 5
In the edges of the placenta of the bitch and of cats, an orange-colored,
crystalline pigment (bilirubin) and a green, amorphous pigment, whose
relation to biliverdin is not clear, have been found.6
From the cotyledons of the placenta in ruminants a white or faintly rose-colored
creamy fluid, the uterine milk, can be obtained by pressure. It is alkaline in
1
A complete review of the investigations of Loeb and his collaborators, with the
literature can be found in Vorlesungen iiber die Dynamik der Lebenserscheinungen,
Leipzig, 1906, s. 239. See also Uber den chemischen Charakter des Befruchtungsvor-
ganges, Leipzig, 1908; Zeitschr. f. physik. Chem. 70, 220 (1910), Arch. f. Entwickelungs-
mech., 31, 658 (1910).
2
Bioch. Zeitschr., 26, 333 (1910).
3
Bottazzi and Dcltino, Centralbl. f. Physiol., 18, 114; Savare, Hofmeister’s, Beitrage,
11; Kikkoji, Zeitschr. f. physiol. Chem., 53.
4
Moscati, Zeitschr, f. physiol. Chem., 53; Lochhead and Cramer, Proc. Roy. Soc,
80 B. (1908).
6
Ascoli, Centralbl. f. Physiol., 16; Raineri, Bioch. Centralbl.. 4, 428; Bergell and
Liepmann, Munch, med. Wochenschr., 1905; Savare, Hofmeister’s Beitrage, 9; Bergell
and Falk, Munch, med. Wochenschr., 55.
6
See Etti, Maly’s Jahresber., 2, 287, and Preyer, Die Blutkristalle, Jena, 1871.
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