scholarly journals Measurement of Differential Na+ Efflux from Apical and Bulk Root Zones of Intact Barley and Arabidopsis Plants

2016 ◽  
Vol 7 ◽  
Author(s):  
Ahmed M. Hamam ◽  
Dev T. Britto ◽  
Rubens Flam-Shepherd ◽  
Herbert J. Kronzucker
Keyword(s):  
Root Zones ◽  
Na Efflux

Nutrient transfer between the root zones of soybean and maize plants connected by a common mycorrhizal mycelium

1991 ◽  
Vol 82 (3) ◽  
pp. 423-432 ◽  
Author(s):  
Gabor J. Bethlenfalvay ◽  
Maria G. Reyes-Solis ◽  
Susan B. Camel ◽  
Ronald Ferrera-Cerrato
Keyword(s):  
Nutrient Transfer ◽  
Root Zones ◽  
Maize Plants

Use of artificial wetland for the treatment of surface and wastewater

1996 ◽  
Vol 33 (4-5) ◽  
pp. 309-313
Author(s):  
Jan Šálek ◽  
František Marcián ◽  
Iman Elazizy
Keyword(s):  
Water Level ◽  
Root Zone ◽  
Artificial Wetland ◽  
Root Zones ◽  
Different Types ◽  
Water Media ◽  
Inlet Zone

Vegetative root zone methods are based on self-purifying processes that take place in the soil, wetland and vegetation containing water media. Our studies are concentrated on the course of puryfying in relation with the length of the filtration bed and on the progress of eliminating the ammoniacal pollution. The research proved that the essential part of the puryfying process takes place within the inlet zone (Figs 1 and 2). The decomposition of ammonia proceeds very slowly. The process of nitrification is affected by the lack of oxygen in the filtration media. To improve the effectiveness of vegetative root zone methods we suggest specific steps: an adjustment of the inlet zone, a system of cascades, a water level pulsation system and combinations of different types and arrangements of vegetative root zones.

The Effect of Temperature on Sodium Movements in Rat Uteri and a Model for Control of their Ion Content

1971 ◽  
Vol 49 (3) ◽  
pp. 240-262 ◽  
Author(s):  
E. E. Daniel ◽  
Kathleen Robinson
Keyword(s):  
Atp Depletion ◽  
Rate Coefficients ◽  
Effect Of Temperature ◽  
Ion Content ◽  
Substantial Fraction ◽  
Cellular Fraction ◽  
Diffusion Controlled ◽  
Na Efflux ◽  
Pinocytotic Vesicles ◽  
Na Uptake

The uptake and efflux of 22Na was studied in isolated rat uterine horns (both fresh and Na-rich) at 5, 15, 25, and 37 °C. Reduction of temperature from 37 °C to 25 or to 15 °C reduced 22Na uptake into, and efflux from, both the extracellular space and cells to the degree expected of a diffusion-controlled process (Q10 < 2). Reduction of the temperature to 5 °C during uptake into Na-rich horns revealed that a substantial fraction of cellular sodium became less exchangeable. At 5 °C, 22Na efflux was also markedly reduced, more than from ouabain or ATP depletion. Analysis of this change by curve-peeling and by reducing the temperature at various stages of efflux suggested that the main cause was a shift of 22Na from the larger, faster cellular fraction (No. 2) to the slower cellular fraction (No. 3). Bound 22Na was also markedly increased. The rate coefficients from curve-peeling for both cellular fractions were decreased. Radioactivity still in fraction 2 at 5 °C emerged at a rate of about half that at 15 °C. However, an overall coefficient for efflux of 22Na which would have emerged in fraction 2 at 15 or 25 °C showed that the Q10 for 22Na efflux between 5 and 15 °C was about 15. Tissues did not swell when they gained sodium at 5 °C. The effects of ouabain to increase 22Na influx and 42K efflux were eliminated at 5 °C. The effects of ATP depletion by iodoacetate and dinitrophenol to decrease 22Na efflux and to increase 22Na uptake, K loss, and swelling were reduced at 5 °C. Prior ATP depletion altered but did not prevent the marked reduction of efflux by cooling to 5 °C. Efflux of lithium, but not of potassium, was markedly slowed at 5 °C. K-free solutions still increased 22Na uptake at 5 °C. A model involving pinocytotic vesicles to explain these and earlier results was postulated.

Na+ Efflux from Apple Dwarfing Rootstocks is Associated with High-Salt Resistance of Their Scions

2020 ◽  
Author(s):  
Xingliang Li ◽  
Minji Li ◽  
Beibei Zhou ◽  
Yuzhang Yang ◽  
Jia Zhou ◽  
...  
Keyword(s):  
Salt Resistance ◽  
High Salt ◽  
Na Efflux ◽  
Dwarfing Rootstocks

Osmoregulation by the Prenatal Spiny Dogfish, Squalus Acanthias

1982 ◽  
Vol 101 (1) ◽  
pp. 295-305 ◽  
Author(s):  
DAVID H. EVANS ◽  
AIMO OIKARI ◽  
GREGG A. KORMANIK ◽  
LEIGH MANSBERGER
Keyword(s):  
Sea Water ◽  
Electrical Potential ◽  
Fluid Flows ◽  
Maternal Plasma ◽  
Water Levels ◽  
Squalus Acanthias ◽  
Rectal Gland ◽  
Na Efflux ◽  
Uterine Fluid ◽  
Electrochemical Equilibrium

Late in gestation of the ovoviviparous dogfish, Squalus acanthias, the uterine fluids are essentially sea water, while the plasma of the ‘pup’ is similar to that of the female, i.e. isotonic to sea water/uterine fluids, with significantly less Na and Cl, and substantial concentrations of urea. Early ‘candle’ embryos are bathed in ‘candle’ fluid and uterine fluid which contains Na and Cl concentrations intermediate between maternal plasma and sea water levels, K concentrations above sea water levels, and urea concentrations slightly below those found in the maternal plasma. Both fluids are isotonic to sea water and maternal plasma. Incubation of ‘candles’ with associated embryos in sea water for 4–6 days resulted in significant increases in ‘candle’ fluid Na and Cl concentrations, and a decline in ‘candle’ fluid K and urea levels. However, under these conditions, the ‘candle’ embryo is still able to regulate plasma Na, Cl, K and urea concentrations. The efflux of Cl is approximately 5 times the efflux of Na from the prenatal ‘pup’; however, both effluxes are equivalent to those described for adult elasmobranchs. The transepithelial electrical potential (TEP) across the ‘pup’ is −4.4 mV in sea water, which indicates that both Na and Cl are maintained out of electrochemical equilibrium. Cloacal fluid flows vary diurnally with Na and Cl concentrations significantly above those of the plasma. Rectal gland efflux can account for 50–100% of the Na efflux, but less than 25% of the Cl efflux. Removal of the rectal gland resulted in an increase in plasma Na and Cl concentrations 48 or 72 h after the operation, but in both cases it appears that some extra rectal gland excretory system balances at least some of the net influx of both salts. Our results demonstrate that even very young ‘candle’ embryos of S. acanthias are capable of osmoregulation, and that older embryos (‘pups') osmoregulate against sea water intra-utero and display the major hallmarks of elasmobranch osmoregulation, including a reduced ionic permeability and a functional rectal gland for net extrusion of NaCl. In addition, it appears that other pathways exist for salt extrusion in addition to the rectal gland. Note:

Acid-Base and Ionic Exchanges at Gills and Kidney After Exhaustive Exercise in the Rainbow Trout

1988 ◽  
Vol 136 (1) ◽  
pp. 461-481 ◽  
Author(s):  
CHRIS M. WOOD
Keyword(s):  
Rainbow Trout ◽  
Exhaustive Exercise ◽  
Strong Ion Difference ◽  
Dynamic Modulation ◽  
Extracellular Acidosis ◽  
Titratable Acid ◽  
Na Efflux ◽  
Net Flux ◽  
Ionic Exchanges ◽  
Net Fluxes

Unidirectional Na+ and Cl− fluxes, net fluxes of Na+, Cl−, other ions, titratable acid (TA), ammonia and acidic equivalents (net H+) across the gills, together with the comparable renal fluxes, were monitored throughout a 24-h period after exhaustive exercise (simple chasing) in the rainbow trout. The gills were the major site of flux. The renal excretion of [TA-HCO3−], ammonia, lactate and most electrolytes increased after exercise, coincident with diuresis. Relative to the gills, the kidney accounted for only 8% of net H+ flux, 0–15% of net electrolyte losses and 50% of lactate loss, though the latter was negligibly small. Approximately 1000 μequiv kg−1 of net H+ were transported across the gills to the water during the first 4h, and then fully recovered over the subsequent 8h, coincident with periods of extracellular acidosis and alkalosis recorded in previous studies. Ammonia efflux increased during the first 4h; changes in titratable acid flux and extracellular PNHNH3 and NH4+ levels suggest that this elevation occurred partially as NH3 diffusion in the first hour, and thereafter mainly as NH4+ exchange. Small net Na+ losses (≊300 μequivkg−1), moderate net K+ losses (≊600 μequiv kg−1) and large net Cl− losses (≊1200 μequiv kg−1) correlated well with previously reported plasma changes; only the Na+ deficit was fully corrected by 24 h. Na+ influx was stimulated and Cl− influx inhibited during the 0–4 h period of net H+ excretion, whereas Na+ influx returned to control levels and Cl− influx increased during the 4–12 h period of net H+ uptake. These data indicate dynamic modulation of Na+/NH4+,H+ and C1−/HCO3−,OH− exchanges; however, an excess of Cl− over Na+ efflux also contributed to net H+ excretion. Acidic equivalent flux correlated well with [Na+-Cl−] net flux, in accord with strong ion difference theory.

Characteristics of active Na transport in intact cardiac cells

1979 ◽  
Vol 236 (2) ◽  
pp. H189-H199 ◽  
Author(s):  
H. G. Glitsch
Keyword(s):  
Heart Muscle ◽  
Muscle Cells ◽  
Cardiac Cells ◽  
Na Transport ◽  
Concentration Gradients ◽  
Experimental Conditions ◽  
Na Pump ◽  
Na Efflux ◽  
Heart Muscle Cells ◽  
K Concentration

An active Na transport maintains the Na and K concentration gradients across the cell membrane of many cells and restores them following excitation. Heart muscle cells display frequent electrical discharges and thus the cardiac Na pump is of fundamental functional significance. Some methods for studying active Na transport are described. The active Na efflux from heart muscle cells is activated by an increase in the intracellular Na and the extracellular K concentration. The linkage between active Na efflux and active K influx varies widely according to the experimental conditions. The cardiac Na pump is electrogenic and can contribute directly to the membrane potential of the cells. The effects of active Na transport on contraction and intercellular coupling in myocardium are discussed.

scholarly journals Effects of anesthesia with the essential oil of Ocimum gratissimum L. in parameters of fish stress

2015 ◽  
Vol 17 (2) ◽  
pp. 215-223 ◽  
Author(s):  
L.L. SILVA ◽  
Q.I. GARLET ◽  
G. KOAKOSKI ◽  
T.A. OLIVEIRA ◽  
L.J.G. BARCELLOS ◽  
...  
Keyword(s):  
Essential Oil ◽  
Blood Collection ◽  
Air Exposure ◽  
Ocimum Gratissimum ◽  
Silver Catfish ◽  
Glucose Levels ◽  
Aerial Parts ◽  
Blood Glucose Levels ◽  
Na Efflux ◽  
Unanesthetized Animals

RESUMO:The effects of anesthesia with the essential oil of Ocimum gratissimum (EOO) in parameters of stress after handling were investigated in silver catfish (Rhamdia quelen). EOO was obtained from the aerial parts by hydrodistillation. Juveniles were anesthetized with 70 or 300 mg L-1 EOO and submitted to air exposure for 1 minute. The fishes were sampled immediately or transferred to anesthetic-free aquaria until sampling. In the first experiment, juveniles had their blood collected at 0, 1, 4, and 8 h after handling to assay plasma cortisol and blood glucose levels. The unanesthetized animals were restrained manually for blood collection. In the second experiment, water samples of the recovery aquaria were collected to evaluate net ion fluxes at 0 - 4 h and 4 - 8 h. Water and ethanol controls were also performed under the same conditions. The results showed that the cortisol levels did not differ among the treatments. Hyperglycemia was verified in fish exposed to 70 and 300 mg L-1 EOO at 1 h and 4 h after handling. After 8 h, cortisol and glucose concentrations were lower or similar than those from immediately after handling for all treatments. EOO anesthesia prevented Na+ efflux observed in the control groups in both flux periods. There were net Cl- and K+ effluxes at 0 - 4 h and influxes at 4 - 8 h after handling in most treatments, and these fluxes did not differ among the treatments. The results suggest that EOO did not impair stress recovery and did not act as an additional handling stressor in silver catfish.

Na+-K+-ATPase-dependent sodium flux in cortical collecting tubule

1988 ◽  
Vol 255 (4) ◽  
pp. F605-F613 ◽  
Author(s):  
M. Blot-Chabaud ◽  
F. Jaisser ◽  
M. Gingold ◽  
J. P. Bonvalet ◽  
N. Farman
Keyword(s):  
Special Device ◽  
Instantaneous Rate ◽  
Sodium Flux ◽  
Na Efflux ◽  
Collecting Tubule ◽  
Pump Activity ◽  
Total Capacity ◽  
Collecting Tubules ◽  
Kinetics Of ◽  
Cortical Collecting Tubule

The instantaneous rate of efflux of intracellular Na was studied in rabbit isolated cortical collecting tubules (CCT) as a function of temperature and intracellular Na concentration ([Na]i). [Na]i of microdissected CCT was increased by cold and K-free exposure in the presence of 22Na and the extracellular tracer [3H] sorbitol. [Na]i rose rapidly to 40 mM at 30 min, after which it rose more slowly, reaching 120-140 mM at 6 h. Kinetics of Na efflux were studied after rapid rewarming, using a special device allowing measurements at 20-s intervals. Under control conditions, the total Na load was extruded in less than 8 min, whereas, in the presence of 10(-4) M ouabain, only 50% of the load was extruded during this period of time. Ouabain-sensitive Na efflux was first evident at 13 degrees C and gradually increased between 13 and 35 degrees C. At 37 degrees C, Na+-K+-ATPase-dependent Na efflux was dependent on [Na]i. This efflux gradually increased, from 0.05 to 0.5 peq.nl tubular volume-1.s-1 as a function of [Na]i and reached a plateau at 70 mM [Na]i. It is concluded that [Na]i is a major modulator of the pump activity in CCT; at normal levels of [Na]i, the pump is operating at only a small fraction of its total capacity.

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