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.

scholarly journals Treatment of a Severe Pediatric Lyell Syndrome with Amniotic Membrane: Case Report and Histological Findings

2018 ◽  
Vol 1 (2) ◽  
pp. 12-21
Author(s):  
B. Azzena ◽  
C. Tiengo ◽  
G. Giatsidis ◽  
R. Salmaso ◽  
A. Pontini
Keyword(s):  
Amniotic Membrane ◽  
Immune Modulation ◽  
Total Body Surface Area ◽  
Supportive Therapy ◽  
Medical Emergency ◽  
Skin Damage ◽  
Mucosal Involvement ◽  
Lyell Syndrome ◽  
Presentation Methods ◽  
Amniotic Membranes

Background: Lyell Syndrome (TEN, Toxic epidermal necrolysis) represents a medical emergency particularly in pediatric patients in whom the massive skin damage can quickly lead to multi-organ dysfunction and death. Prompt restoration of the physiologic mucosal/cutaneous barrier is mandatory. The use of amniotic membranes has been described in the treatment of ophthalmic Lyell Syndrome, but its use has not yet been adopted for the management of larger cutaneous wounds. Study Hypothesis: Here we report the use of amniotic membranes in a pediatric case of severe Lyell Syndrome with complete skin surface, ocular and mucosal involvement with life threating presentation. Methods: A 7-year old female was admitted to our Burn Centre for severe cutaneous/mucosal exfoliation (100% Total body surface area, TBSA) as a result of an adverse reaction to ibuprofen administration. Supportive fluid administration, cardiac-pulmonary assistance and pain management were complemented by serial grafting of amniotic membranes on all affected areas to provide coverage of the exfoliated skin/mucosa. Biopsies were obtained to monitor histological skin changes. Results: The patient showed an excellent response to amniotic membrane treatment, with rapid restoration of mucosal and cutaneous layers in the grafted areas. This resulted in a decreased need for dressing changes, avoidance of additional surgeries and a reduced dependence on supportive therapy. Lower pain levels than usually expected led to a reduced need for narcotic pain medications and allowed for early physical rehabilitation and a short hospital stay. Histology confirmed evidence of topical immune-modulation in treated areas (reduction of inflammatory infiltrate). Conclusion: As we tested in numerously TEN and burn pediatric injuries Amniotic membranes with their regenerative and immune-modulatory effects may represent an life saving treatment even in the worst cases of pediatric Lyell syndrome.

Leukotrienes C4 and D4 do not increase filtration coefficient of excised perfused guinea pig lungs

1987 ◽  
Vol 62 (1) ◽  
pp. 1-9 ◽  
Author(s):  
R. K. Albert ◽  
G. Greenberg ◽  
R. J. Guest ◽  
D. Luchtel ◽  
W. R. Henderson
Keyword(s):  
Guinea Pig ◽  
Hydrostatic Stress ◽  
Filtration Coefficient ◽  
Direct Effects ◽  
Lung Weight ◽  
Fluid Filtration ◽  
Flow Perfusion ◽  
Pulmonary Arterial ◽  
The Mean ◽  
Perfusion Period

We tested the direct effects of leukotriene (LT) C4 or D4 on the pulmonary vascular fluid filtration coefficient (Kf) by adding these LT's to the cell-depleted perfusate of excised guinea pig lungs. Pulmonary arterial (Ppa) and airway (Paw) pressures were monitored, and left atrial pressure was kept constant during 10 min of constant-flow perfusion. Kf's were then calculated by two methods [Drake and colleagues (KfD), Am. J. Physiol. 234 (Heart Circ. Physiol. 3): H266-H274, 1978; and Goldberg (KfG), Am. J. Physiol. 239 (Heart Circ. Physiol. 8): H189-H198, 1980] from the change in lung weight resulting from a no-flow zone 3 hydrostatic stress applied for 20 min. With no LT's (Tyrode's buffer alone), the mean +/- SE Paw was 9.0 +/- 0.7 cmH2O and the Ppa was 14.2 +/- 1.1 cmH2O throughout the 10-min perfusion. The KfD and KfG were 1.239 +/- 0.169 and 1.586 +/- 0.223 ml X min-1 X mmHg-1 X 100 g lung-1, respectively. The mean +/- SE lung wet-to-dry ratio (W/D) after the 20-min hydrostatic stress was 16.7 +/- 1.6. Within 30–45 s of adding 4 micrograms of LTC4 or LTD4, Paw and Ppa both increased and remained elevated throughout the perfusion period. The KfD and KfG were 1.586 +/- 0.223 and 2.071 +/- 0.234 ml X min-1 X mmHg-1 X 100 g lung-1, respectively, and the W/D was 18.1 +/- 1.7 after LTC4 (all P greater than 0.4 compared with Tyrode's buffer alone) and 1.417 +/- 0.200 and 1.851 +/- 0.244 ml X min-1 X mmHg-1 X 100 g lung-1, respectively, with a W/D of 20.5 +/- 1.3 after LTD4 (all P greater than 0.4 compared with Tyrode's buffer alone).(ABSTRACT TRUNCATED AT 250 WORDS)

Perfusion rates and the transfer of water across isolated guinea pig placenta

1977 ◽  
Vol 232 (6) ◽  
pp. H666-H670
Author(s):  
H. Schroder ◽  
H. P. Leichtweiss
Keyword(s):  
Guinea Pig ◽  
Flow System ◽  
Tritiated Water ◽  
Countercurrent Flow ◽  
Concurrent System ◽  
Flow Rates ◽  
Guinea Pig Placenta ◽  
The Subject ◽  
Pig Placenta ◽  
Relative Transfer

The transfer of tritiated water across the isolated, artificially perfused guinea pig placenta was the subject of 21 experiments. The observed relationship between the flow rates and the relative transfer of water cannot be explained by a concurrent or pool-flow system. If the direction of the fetal flow is reversed, the rate of transfer is lowered. It may be concluded, that the decrease is a result of a change from a nonideal countercurrent flow system to a nonideal concurrent system. This conclusion, however, holds only if all other parameters that determine the exchange as well remain unaffected. In the range of flows investigated, the transfer of water is flow limited.

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 Transport of Salt and Water in Rabbit and Guinea Pig Gall Bladder

1964 ◽  
Vol 48 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Jared M. Diamond
Keyword(s):  
Gall Bladder ◽  
Guinea Pig ◽  
Fluid Transport ◽  
Water Movement ◽  
Bladder Wall ◽  
Nacl Transport ◽  
Exogenous Glucose ◽  
Gall Bladder Wall ◽  
Reproducible Method

A simple and reproducible method has been developed for following fluid transport by an in vitro preparation of mammalian gall bladder, based upon weighing the organ at 5 minute intervals. Both guinea pig and rabbit gall bladders transport NaCl and water in isotonic proportions from lumen to serosa. In the rabbit bicarbonate stimulates transport, but there is no need for exogenous glucose. The transport rate is not affected by removal of potassium from the bathing solutions. Albumin causes a transient weight loss from the gall bladder wall, apparently by making the serosal smooth muscle fibers contract. Active NaCl transport can carry water against osmotic gradients of up to two atmospheres. Under passive conditions water may also move against its activity gradient in the presence of a permeating solute. The significance of water movement against osmotic gradients during active solute transport is discussed.

scholarly journals Sutureless Amniotic Membranes (ProKera) for Filamentary Keratitis: A Case Series

2019 ◽  
Vol 2 (1) ◽  
pp. e10-e16
Author(s):  
Jennifer S Harthan ◽  
Lindsay A Sicks
Keyword(s):  
Amniotic Membrane ◽  
Ocular Surface ◽  
Management Strategies ◽  
Anterior Segment ◽  
Case Series ◽  
Signs And Symptoms ◽  
Traditional Therapies ◽  
Amniotic Membranes ◽  
Ocular Signs

Purpose To report a case series of refractory filamentary keratitis successfully managed with sutureless amniotic membranes resistant to other management strategies.   Methods Three cases are discussed with anterior segment photography who were diagnosed with filamentary keratitis and successfully managed with sutureless amniotic membranes, after experiencing limited relief with standard treatments.   Conclusions This case series demonstrates the complex management of patients with filamentary keratitis who had failed with traditional therapies and were successfully managed with sutureless amniotic membranes. All three patients demonstrated improvement in both ocular signs and symptoms following amniotic membrane application to the ocular surface. 

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