The effect of prolactin on sodium flux through the isolated amniotic membrane of the guinea pig

1977 ◽  
Vol 55 (9) ◽  
pp. 1468-1474 ◽  
Author(s):  
W. F. Holt ◽  
A. M. Perks
Keyword(s):  
Amniotic Fluid ◽  
Base Line ◽  
Line Flux ◽  
Partial Explanation ◽  
Diffusional Flux ◽  
Unidirectional Flux ◽  
Flow Perfusion ◽  
Sodium Flux ◽  
Amniotic Membranes ◽  
Initial Base

Amniotic membranes from fetal guinea pigs (0.46–0.87 of term) were maintained in a continuous-flow perfusion cell, with amniotic saline on both surfaces. Prolactin (10 μg/ml; fetal surface) increased the unidirectional diffusional flux of 22Na+ in the fetal–maternal direction (maximum, about 75%; average over 3rd h, 53.6 ± 10.1%). This increase was significant when compared with albumin controls (P < 0.05) and with the initial base-line fluxes (P < 0.01). Albumin controls showed no significant change from the base-line flux. Therefore, prolactin appeared to increase the unidirectional flux of sodium out of the potential amniotic cavity.One membrane, at term and overdue, failed to respond.Experiments on the reverse, maternal–fetal flux of 22Na+ showed no differences between membranes treated with prolactin or albumin. Therefore, prolactin had no effect on the unidirectional flux of sodium into the potential amniotic cavity.Sodium permeability rose dramatically in membranes close to birth or overdue; 22Na+ fluxes increased about 20-fold in both directions.Prolactin appears capable of causing a net movement of sodium through the amnion, out of the amniotic fluid. Also, it is able to slow the movement of water in the same direction. These factors, taken together, suggest a partial explanation for the maintenance of a hypotonic amniotic fluid.

scholarly journals ARCH-COMP 2019 Category Report: Falsification

10.29007/68dk ◽  
2019 ◽  
Author(s):  
Gidon Ernst ◽  
Paolo Arcaini ◽  
Alexandre Donzé ◽  
Georgios Fainekos ◽  
Logan Mathesen ◽  
...  
Keyword(s):  
Temporal Logic ◽  
State Of The Art ◽  
Cyber Physical Systems ◽  
The State ◽  
Base Line ◽  
Physical Systems ◽  
The Future ◽  
Friendly Competition ◽  
Initial Base

This report presents the results from the 2019 friendly competition in the ARCH workshop for the falsification of temporal logic specifications over Cyber-Physical Systems. We describe the organization of the competition and how it differs from previous years. We give background on the participating teams and tools and discuss the selected benchmarks and results. The benchmarks are available on the ARCH website1, as well as in the competition’s gitlab repository2. The main outcome of the 2019 competition is a common benchmark repository, and an initial base-line for falsification, with results from multiple tools, which will facilitate comparisons and tracking of the state-of-the-art in falsification in the future.

Fetal recirculation of amniotic fluid arginine vasopressin

1986 ◽  
Vol 250 (3) ◽  
pp. E253-E258
Author(s):  
M. G. Ervin ◽  
M. G. Ross ◽  
R. D. Leake ◽  
D. A. Fisher
Keyword(s):  
Amniotic Fluid ◽  
Arginine Vasopressin ◽  
Urine Volume ◽  
Fetal Lung ◽  
Biologically Active ◽  
Base Line ◽  
Lung Fluid ◽  
Fetal Plasma ◽  
Urine Production ◽  
Fetal Urine

Amniotic fluid volume reflects a balance between fetal lung fluid and fetal urine production and fluid reabsorption via fetal swallowing. Arginine vasopressin (AVP) infusion decreases both fetal lung fluid and urine production and increases amniotic fluid osmolality and AVP concentration. In the present study we assessed the effect of amniotic fluid AVP injection on plasma AVP (n = 6) and renal function (n = 4) in chronically catheterized fetal lambs (X gestation = 130 days). Thirty minutes after addition of 25 micrograms of synthetic AVP into the amniotic cavity, mean +/- SE fetal plasma AVP increased from a base line of 2.7 +/- 0.2 to 14.6 +/- 3.4 pg/ml (P less than 0.01). One hundred and twenty minutes after injection, plasma AVP had increased to 26.9 +/- 5.7 pg/ml. Fetal urine volume did not change (0.78 +/- 0.01 ml/min) but significant increases in urine osmolality (169 +/- 19 to 315 +/- 25 mosm) and urine sodium (64 +/- 11 to 125 +/- 11 mueq/ml) were observed 120 min after AVP administration. In conclusion, amniotic fluid AVP levels can affect fetal plasma AVP concentration, and AVP absorbed from the amniotic fluid by the fetus remains biologically active.

Human amniotic fluid mathematical model: Determination and effect of intramembranous sodium flux

1998 ◽  
Vol 178 (3) ◽  
pp. 484-490 ◽  
Author(s):  
Mark A. Curran ◽  
Mark J.M. Nijland ◽  
Stephanie E. Mann ◽  
Michael G. Ross
Keyword(s):  
Mathematical Model ◽  
Amniotic Fluid ◽  
Human Amniotic Fluid ◽  
Sodium Flux ◽  
Model Determination

Simonart syndrome: a brief review of the literature and your own observation

2020 ◽  
Author(s):  
L.I. Pavlenko, S.A. Gribova
Keyword(s):  
Prenatal Diagnosis ◽  
Amniotic Fluid ◽  
Premature Birth ◽  
Review Of The Literature ◽  
External Examination ◽  
Ultrasound Study ◽  
Amniotic Membranes

A case of prenatal diagnosis of Simonart syndrome (syndrome of amniotic constrictions) is presented. An amnioscopic operation was performed — dissection of the ligaments. There was an outpouring of amniotic fluid due to a high rupture of the amniotic membranes and premature birth at 28 weeks of gestation. During the external examination of the newborn, the data obtained during the ultrasound study was fully confirmed.

scholarly journals Characteristics of Sodium Flux from Serosa to Mucosa in Rabbit Ileum

1974 ◽  
Vol 64 (3) ◽  
pp. 274-292 ◽  
Author(s):  
Jehan-F. Desjeux ◽  
Y.-H. Tai ◽  
Peter F. Curran
Keyword(s):  
Electrical Potential ◽  
Secretory Process ◽  
Rabbit Ileum ◽  
Shunt Pathway ◽  
Diffusional Flux ◽  
Transcellular Pathway ◽  
Sodium Flux ◽  
Secretory Transport ◽  
Paracellular Shunt

Sodium flux from serosa to mucosa, JsmNa in rabbit ileum in vitro has been studied as a function of applied electrical potential at equal sodium concentrations in the bathing solutions. The results indicate that JsmNa involves two pathways, a diffusional flux through a paracellular shunt pathway and a flux that is independent of applied potential and presumably involves a transcellular pathway. The latter pathway comprises approximately 25 % of JsmNa in Ringer's solution containing 10 mM glucose and 25 mM bicarbonate. It is stimulated significantly by theophylline unaffected by removal of glucose or addition of ouabain but is reduced to negligible values by anoxia, dinitrophenol, and replacement of all chloride and bicarbonate by isethionate. Thus this component of JsmNa has a number of characteristics consistent with involvement in a specific secretory process mediating an electrically neutral secretory transport of sodium plus anion from serosa to mucosa. In addition to stimulating this process, theophylline significantly reduced the permeability of the paracellular shunt pathway to sodium.

The Availability of Cortisol in Amniotic Fluid to the Fetus and Chorionic and Amniotic Membranes*

Endocrinology ◽  
1979 ◽  
Vol 104 (4) ◽  
pp. 1053-1058 ◽  
Author(s):  
GEORGE D. CARSON ◽  
JOHN D. BOLLA ◽  
JOHN R. G. CHALLIS
Keyword(s):  
Amniotic Fluid ◽  
Amniotic Membranes

The influence of vasopressin on the passage of tritiated water through the isolated amniotic membrane and other tissues from the fetal guinea pig

1977 ◽  
Vol 55 (9) ◽  
pp. 1393-1403 ◽  
Author(s):  
W. F. Holt ◽  
A. M. Perks
Keyword(s):  
Guinea Pig ◽  
Amniotic Membrane ◽  
Outer Surface ◽  
Continuous Flow ◽  
Water Movement ◽  
Tritiated Water ◽  
Fetal Skin ◽  
Flow Perfusion ◽  
Transient Rise ◽  
Amniotic Membranes

Amniotic membranes from fetal guinea pigs (0.62–1.00 of term), were kept in a continuous-flow perfusion cell. Vasopressin (50–500 mU/ml; fetal surface) increased the unidirectional maternal–fetal flux of 3H2O by up to 12.3 ± 1.5%. The corresponding reverse flux increased only 1.6%. The responses in the maternal–fetal direction showed a linear relationship with the log dose of vasopressin. Over the same period (35 min), there was a 13.6 ± 6.3% increase in the maternal–fetal flux of 22Na+. Therefore, vasopressin may influence water movement by an effect on ions, such as Na+ or Cl−.Isolated midterm fetal skin showed closely similar effects; vasopressin (500–1000 mU/ml; outer surface) increased the amniotic–fetal flux of 3H2O by up to 30.4 ± 13.7%. The late-term fetal bladder responded to vasopressin (100 mU/ml; outer, serosal surface), by increasing the flux of 3H2O from lumen to fetus by 49.4 ± 17.8%; one bladder showed a transient rise close to 85%.The sensitivities of the skin and amnion were similar, but the bladder was about 12 times more sensitive to vasopressin. The possibility that vasopressin influences an extraplacental route for the supply of water to the fetus, through the amnion, skin, and bladder, is suggested.

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