III.—On the Source of the Amniotic and Allantoic Fluids in Mammals

Abstract

In all vertebrates, as the embryo develops at one pole of the egg, it sinks inwards till it becomes completely enclosed in a hood or sac filled with fluid, the amnion. When the sac or true amnion has completely closed over the embryo, it becomes separated from the outer layer, which remains in contact with the covering of the egg as the false or chorionic amnion.

Division of the common mammals into two groups according to the concentration of fructose in the blood of the foetus

“…Some authors have attributed to Giirber & Griinbaum the demonstration of fructose in other species (the horse and sheep). Paton, Watson & Kerr (1907) claimed that the amniotic and allantoic fluids of the sheep and cow contained fructose, but they also discussed other species in a way that is difficult to follow. There can be little doubt that these authors believed that their findings for the sheep and cow applied to the foetus generally and thus, in addition to allowing several different interpretations of their results (Orr, 1924;Needham, 1931;Bacon & Bell, 1948; Barklay, Haas, Huggett, King & Rowley, 1949;Huggett & Hammond, 1952), they engendered an assumption that fructose was a universal feature of foetal life.…”

Analysis of Transport in the Compartments of the Sheep Fetus

“…Figures la and b relate allantoic and amniotic volumes to time, as found by different authors [6,12,15,18]. The relations of ionic con centrations to time in figures 2-4 were provided as linear approxima tions by M a n n et al [unpublished], as was the relation of cp2 and <pK to time in figure 5.…”

“…The Na+ and K+ concentrations of the allantoic and amniotic compartments, and of maternal blood and fetal urine, were provided as a function of duration of gestation by Mann, Curet, Abrams and Baron [unpublished]. These concentrations are related to urine flow and compartmental volumes as obtained from the litera ture [6,12,15,18], in order to calculate net volume and ionic move ments (table II). Mann et al [unpublished] also provided for the first time measurements of the allantoic-maternal electrical potential as a function of duration of gestation.…”

Amniotic Fluid Volume and Experimentally-Induced Congenital Malformations

“…S tu d ies o f th e am n io tic fluid volum e o f cow, sheep, sow , ra b b it, cat, guinea pig, h a m ste r, r a t, a n d m ouse (7)(8)(9)(10)(11)(12)(13)(14)(15)(16) h av e been m ade. B u t in all cases m e a su re m e n t w as b y m eans o f g ra d u a te s, syringes, o r p i p e tte s.…”

“…3, 4), esophageal atre sia (5), and o th e r co n g en ital m alfo rm atio n s (6) m ay be in d u ced in exp erim en tal m am m alian species are w ell know n. B u t before stu d ies could be s ta rte d to in v e stig a te th e relatio n sh ip o f congenital m alfo rm atio n s a n d am n io tic fluid, it w as necessary to devise a m e th o d for th e volu m etric d e te rm in a tio n o f re la tiv e ly sm all am o u n ts o f am n io tic fluid 1 This study was supported in part by Grant RG-7107 from the National Institute of Arthritis and Metabolic Diseases, National Institutes of Health, United States Public Health Service, and a NATO Fellowship to one of us (R. G.). th a t is m ore precise an d reliable th a n the d irect m ethods used in p a st an im al stu d ies (7)(8)(9)(10)(11)(12)(13)(14)(15)(16).…”