Vesicular uptake of albumin in human amnion – implications in amniotic fluid regulation

Placenta ◽  
2016 ◽  
Vol 45 ◽  
pp. 112
Author(s):  
Margarita Sharshiner ◽  
Cecilia Cheung ◽  
Robert Brace
Keyword(s):  
Amniotic Fluid ◽  
Human Amnion ◽  
Fluid Regulation ◽  
Vesicular Uptake

118. THE PRORENIN RECEPTOR/PLZF PATHWAY IN HUMAN AMNION

2010 ◽  
Vol 22 (9) ◽  
pp. 36
Author(s):  
K. G. Pringle ◽  
A. L. Conquest ◽  
C. M. Mitchell ◽  
T. Zakar ◽  
E. R. Lumbers
Keyword(s):  
New Zealand ◽  
Amniotic Fluid ◽  
Mrna Levels ◽  
The Novel ◽  
Quantitative Real Time Pcr ◽  
Human Amnion ◽  
Reproductive Tissues ◽  
Prorenin Receptor ◽  
Human Reproductive ◽  
Neonatal Physiology

Prorenin, despite being inactive, is the major form of renin found in amniotic fluid and reproductive tissues. Prorenin becomes active if it binds to the novel prorenin receptor (ATP6AP2). The prorenin-ATP6AP2 complex has been found to stimulate translocation of Promyelocytic Zinc Finger (PLZF) protein to the nucleus where it increases expression of the p85α subunit of PI3 kinase (PI3K-p85α) and represses the expression of ATP6AP21. Progesterone and glucocorticoids have also been shown to stimulate PLZF2, 3. We aimed to find out if PLZF and the prorenin-ATP6AP2 pathway interact in human reproductive tissues. Human amnion was cultured for 24 h in media containing vehicle, dexamethasone, amniotic fluid or recombinant human (rh) prorenin. Total RNA was extracted using TRIZol® and converted to cDNA for quantitative real-time PCR using SuperScript III and random hexamers. mRNA abundances for PLZF, PI3K-p85α and ATP6AP2 were calculated relative to Alien RNA using the ΔΔCT method. Our preliminary data show that exposure of amnion explants to dexamethasone upregulates PLZF and PI3K-p85α mRNA but has no effect on ATP6AP2. Culture of amnion explants with amniotic fluid also increases PLZF but does not change PI3K or ATP6AP2. In contrast, culture of amnion explants with (rh) prorenin increases PI3K mRNA but not PLZF or ATP6AP2. As expected, dexamethasone affects PLZF expression, however in amnion there is no interaction with the ATP6AP2 pathway. In addition, we believe we have identified a novel prorenin/ATP6AP2 signalling pathway which acts on PI3K-p85α independent of PLZF. In contrast to these data, amniotic fluid increases PLZF but not PI3K-p85α mRNA levels suggesting that amniotic fluid contains other factors that oppose prorenin and glucocorticoid effects on PI3K-p85α. (1) Schefe, J.H., et al. Circ Res, 2006. 99(12): 1355–1366.(2) Fahnenstich, J., et al. Mol. Hum. Reprod., 2003. 9(10): 611–623.(3) Conquest, A. et al. Fetal and Neonatal Physiology Workshop, 2010. Wellington, New Zealand.

scholarly journals The soluble antigens of varicella-zoster virus produced in tissue culture

1961 ◽  
Vol 59 (2) ◽  
pp. 249-257 ◽  
Author(s):  
Anne E. Caunt ◽  
C. J. M. Rondle ◽  
A. W. Downie
Keyword(s):  
Tissue Culture ◽  
Amniotic Fluid ◽  
Good Yield ◽  
Complement Fixation ◽  
Tissue Cultures ◽  
Human Amnion ◽  
Varicella Zoster ◽  
Vesicle Fluid ◽  
Infected Cells ◽  
Virus Strains

It has been found that antigens suitable for routine tests for complement-fixing or precipitating antibodies in the sera of suspected cases of chickenpox or zoster can be readily prepared from tissue cultures of human amnion infected with zostervaricella virus.Useful antigens were obtained when infected cells were incubated at 36°–38° C. in bovine amniotic fluid diluted with an equal volume of Hanks' solution.Virus strains gave a good yield of antigen after two or more passages in tissue culture but one strain in its fiftieth passage did not.Harvested culture fluids require 5- to 20-fold concentration for complement-fixation tests and 100- to 200-fold for precipitation tests; concentration of culture fluids was readily effected by drying from the frozen state after removal of salts by dialysis. Tissue culture antigens gave results by complement-fixation tests which were comparable to those given by a good vesicle fluid.Some evidence was obtained that the antigens responsible for precipitation were not identical with those fixing complement with convalescent sera.

Nitric oxide modulates spontaneous swallowing behavior in near-term ovine fetus

1999 ◽  
Vol 277 (4) ◽  
pp. R981-R986 ◽  
Author(s):  
Mostafa A. El-Haddad ◽  
Conrad R. Chao ◽  
Sheng-Xing Ma ◽  
Michael G. Ross
Keyword(s):  
Nitric Oxide ◽  
Amniotic Fluid ◽  
Repeated Measures ◽  
Lateral Ventricle ◽  
Low Voltage ◽  
Control Period ◽  
Brain Regions ◽  
No Synthase ◽  
Fluid Regulation ◽  
Control Study

Human and ovine fetuses demonstrate an enhanced rate of swallowing, an activity critical for amniotic fluid regulation. Fetal swallowing may be modulated by both systemic and central factors. Nitric oxide (NO) is a central neuromodulator that has been localized to brain regions regulating thirst and swallowing. We sought to determine if NO contributes to the regulation of spontaneous ovine fetal swallowing. Six time-dated pregnant ewes with singleton fetuses (129 ± 1 day) were chronically prepared with fetal vascular and lateral ventricle catheters and electrocorticogram (ECoG) and esophageal electromyogram electrodes. After a 2-h control period, fetuses were given lateral ventricle injection of NO synthase inhibitor nitro-l-arginine methyl ester (l-NAME) and monitored for 2 h. NO precursor l-arginine was then injected into the lateral ventricle, and fetuses were monitored for a final 2 h. All fetuses received an additional control study of fetal swallowing before and after lateral ventricle injection of artificial cerebrospinal fluid (aCSF). Data were analyzed with repeated-measures ANOVA and paired t-test ( P < 0.05). Suppression of a central NO with central l-NAME significantly reduced mean (±SE) spontaneous fetal swallowing (1.2 ± 0.1–0.6 ± 0.1 swallows/min low-voltage ECoG; P < 0.01). Restoration of central NO by l-arginine significantly increased fetal swallowing to pre-l-NAME levels (1.2 ± 0.1 swallows/min low voltage). There were no changes in fetal swallowing during the control study of aCSF. Fetal ECoG activity and blood pressure did not change during the study or control aCSF injection. We conclude that NO is an important neuromodulator of fetal swallowing activity. Central NO synthase activity may contribute to the heightened level of spontaneous fetal swallowing and thus amniotic fluid regulation.

Comparison of the specific binding of cortisol in human amnion, amniotic fluid, and plasma

1987 ◽  
Vol 65 (1) ◽  
pp. 54-59 ◽  
Author(s):  
L. Riopel ◽  
W. Gibb
Keyword(s):  
Amniotic Fluid ◽  
Concanavalin A ◽  
Specific Binding ◽  
Binding Protein ◽  
Maternal Plasma ◽  
Binding Activity ◽  
Human Amnion ◽  
Corticosteroid Binding Globulin ◽  
Influence Of Ph ◽  
Contraceptive Treatment

The purpose of this study was to compare the specific cortisol-binding protein found associated with human amnion with specific cortisol binding in human amniotic fluid and plasma. The electrophoretic mobility on polyacrylamide gels of the specific cortisol binding in amnion, amniotic fluid, and maternal plasma was identical. The influence of pH on cortisol binding activity was similar in all tissues and the cortisol binding was immunoprecipitable by a polyclonal antibody raised against human corticosteroid-binding globulin. The interaction of the cortisol binding protein with concanavalin A was studied in preterm amniotic fluid, term amniotic fluid, term amnion, and plasma from pregnant women at term and women under oral contraceptive treatment. Binding to concanavalin A was similar in term amnion and term amniotic fluid but was less than that found with both preterm amniotic fluid and term plasma. These results indicate that the cortisol binding portein associated with human amnion has similar characteristics to plasma corticosteroid-binding globulin, but that its state of glycosylation appears to be more like that of the cortisol binding protein in term amniotic fluid rather than in plasma.

scholarly journals Identification of 9α,11β-Prostaglandin F2 in Human Amniotic Fluid and Characterization of Its Production by Human Gestational Tissues

2005 ◽  
Vol 90 (7) ◽  
pp. 4244-4248 ◽  
Author(s):  
Murray D. Mitchell ◽  
Maxwell C. Chang ◽  
Tinnakorn Chaiworapongsa ◽  
Hao-Yi Lan ◽  
Rachel J. A. Helliwell ◽  
...  
Keyword(s):  
Amniotic Fluid ◽  
Late Gestation ◽  
Human Amniotic Fluid ◽  
Human Amnion ◽  
Related Substances ◽  
Human Labor ◽  
Gestational Tissues ◽  
First Time ◽  
Wall Components

Abstract Context: 9α,11β-Prostaglandin F2 (9α,11β-PGF2) can contract uterine smooth muscle with a potency equal to PGF2α. Its presence in the human uterus and production by human gestational tissues is unknown. Objective: These studies were performed to determine whether the PGD2-derived 9α,11β-PGF2 is both present in human amniotic fluid and synthesized by human gestational tissues and if so, whether labor-related substances could regulate its production. Results: Detectable concentrations of 9α,11β-PGF2 were found in amniotic fluid samples and appeared to increase in late gestation. All gestational tissues studied synthesized 9α,11β-PGF2, with the placenta having the highest basal production rate, followed by the amnion and then the choriodecidua. IL-1β and TNFα caused concentration-dependent increases in 9α,11β-PGF2 production in human amnion and choriodecidual explants. Moreover, treatment of choriodecidual and placental explants with lipopolysaccharide resulted in a significant increase in 9α,11β-PGF2 production rates, reaching a maximum of 13-fold in the choriodecidua. Studies examining the effects of the addition of exogenous PGD2 strongly indicated that the choriodecidua has significant ability to convert PGD2 to 9α,11β-PGF2, whereas the amnion has little. Conclusions: These results demonstrate for the first time that 9α,11β-PGF2 is present in human amniotic fluid and that it is produced by human gestational tissues and up-regulated by bacterial cell wall components and proinflammatory cytokines. We suggest that this prostaglandin may play a part in the mechanisms of human labor at term and preterm.

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