In Early post-implantation stages of development, before the establishment of an intimate relationship between the maternal and foetal circulations, embryonic nutrition is carried out largely by the breakdown of macro-molecules in certain phagocytic extra-embryonic membranes. This communication is concerned with defining histochemica, electron microscopic and biochemical parameters which make it possible to identify the membranes concerned. In vivo and in vitro systems for the measurement of the amount of macromolecular breakdown occurring in certain foetal membranes are presented. It is suggested that interference with these catabolic processes may produce congenital malformations or result in abortion of the conceptus.
References
1.
AbrahamR. (1967). Lysosomal aryl sulphatase in the liver. Histochemie11, 129.
2.
BeckF., LloydJ. B., & GriffithsA. (1967). A histochemical and biochemical study of some aspects of placental function in the rat using maternal injection of horseradish peroxidase. J. Anat.101, 461.
3.
BrambellF. W. R. (1966). The transmission of immunity from mother to young and the catabolism of immunoglobulins. Lancet 1966 2, 1087.
4.
CohnZ. A. (1966). The regulation of pinocytosis in mouse macrophages. I. Metabolic requirements as defined by the use of inhibitors. J. exp. Med.124, 557.
5.
CohnZ. A., & ParksE. (1967a). The regulation of pinocytosis in mouse macrophages. II. Factors inducing vesicle formation. J. exp. Med.125, 213.
6.
CohnZ. A., & ParksE. (1967a). The regulation of pinocytosis in mouse macrophages. III. The induction of vesicle formation by nucleosides and nucleotides. J. exp. Med.125, 457.
7.
CreedR. F. S., & BiggersJ. D. (1964). Placental haemophagous organs in Procyonidae and Mustelidae. J. Reprod. Fert.8, 133.
8.
De DuveC., & WattiauxR. (1966). Functions of lysosomes. A. Rev. Physiol.28, 435.
9.
GomoriG. (1952). Microscopic histochemistry: principles and practice.Chicago: University of Chicago Press.
10.
GrahamR. C., & KarnovskyM. J. (1966). The early stages of absorption of injected horseradish peroxidase in the proximal tubules of mouse kidney: ultrastructural cytochemistry by a new technique. J. Histochem. Cytochem.14, 291.
11.
Krzyzowska-GrucaS., & SchieblerT. H. (1967). Experimentelle Untersuchungen am Dottersackepithel der Ratte. Z. Zellforsch, mikrosk. Anat.79, 157.
12.
LloydJ. B., BeckF., GriffithsA., & ParryL. M. (1968). The mechanism of action of acid bisazo dyes. In Biological Council symposium on the interaction of drugs and subcellular components in animal cells (ed. CampbellP. N.), p. 171. London: Churchill.
13.
LowryO. H., RosebroughN. J., FarrA. L., & RandallR. J. (1951). Protein measurement with the Folin phenol reagent. J. biol. Chem.193, 265.
14.
NovikoffA. B., EssnerE., & QuintanaN. (1964). Golgi apparatus and lysosomes. Fedn Proc. Fedn Am. Socs exp. Biol.23, 1010.
15.
ParryL. M., BeckF., & LloydJ. B. (1968). In vitro measurement of intracellular digestion. J. Anat.103, 393.
16.
SchultzP. W., RegerJ. F., & SchultzR. L. (1966). Effects of Triton WR 1339 on the rat yolk-sac placenta. Am. J. Anat.119, 199.
17.
StrausW. (1962). Colorimetric investigation of the uptake of an intravenously injected protein (horseradish peroxidase) by rat kidney and effects of competition by egg white. J. Cell Biol.12, 231.
18.
StrausW. (1964). Factors affecting the state of injected horseradish peroxidase in animal tissues and procedures for the study of phagosomes and phago-lysosomes. J. Histochem. Cytochem.12, 470.
19.
WislockiG. B., & BennettH. S. (1943). The histology and cytology of the human and monkey placentae with special reference to the trophoblast. Am. J. Anat.73, 335.
