Urine flow and the role of the antennal glands in water balance during aerial exposure in the crayfish,Austropotamobius pallipes (Lereboullet)

1986 ◽  
Vol 156 (4) ◽  
pp. 529-535 ◽  
Author(s):  
R. Tyler-Jones ◽  
E. W. Taylor
Keyword(s):  
Water Balance ◽  
Urine Flow ◽  
Aerial Exposure ◽  
Austropotamobius Pallipes ◽  
Antennal Glands

Salt and Water Balance of the Spiny Lobster, Panulirus Argus: The Role of the Antennal Glands

1977 ◽  
Vol 70 (1) ◽  
pp. 221-230
Author(s):  
D. F. MALLEY
Keyword(s):  
Water Balance ◽  
Sea Water ◽  
Spiny Lobster ◽  
Water Levels ◽  
Panulirus Argus ◽  
Antennal Glands ◽  
Salt And Water Balance

1. Panulirus argus in full sea water differs from most other marine isosmotic decapods by regulating Cl− levels in the haemolymph slightly below those in sea water and by having haemolymph K+ levels similar to those in sea water. The species is typical in regulating haemolymph Na+ and Ca2+ above, and Mg2+ and SO42- below, sea-water levels of these ions. Its haemolymph Mg2+ and SO42- concentrations are amongst the lowest reported in marine decapods. 2. The antennal glands contribute to this regulation of Mg2+ SO42- and Cl− by producing urine with markedly, and approximately equally, elevated Mg2+ and SO42- levels, and slightly elevated Cl− levels, compared with those in the haemolymph. The antennal glands show a small tendency to conserve water. Note: Freshwater Institute, 501 University Crescent, Winnipeg, Manitoba, Canada R3T 2N6.

Role of renal medullary adenosine in the control of blood flow and sodium excretion

1999 ◽  
Vol 276 (3) ◽  
pp. R790-R798 ◽  
Author(s):  
Ai-Ping Zou ◽  
Kasem Nithipatikom ◽  
Pin-Lan Li ◽  
Allen W. Cowley
Keyword(s):  
Blood Flow ◽  
Sodium Excretion ◽  
Renal Medulla ◽  
Urine Flow ◽  
Doppler Flowmetry ◽  
Blood Flows ◽  
Medullary Blood Flow ◽  
Adenosine Concentration ◽  
Interstitial Infusion

This study determined the levels of adenosine in the renal medullary interstitium using microdialysis and fluorescence HPLC techniques and examined the role of endogenous adenosine in the control of medullary blood flow and sodium excretion by infusing the specific adenosine receptor antagonists or agonists into the renal medulla of anesthetized Sprague-Dawley rats. Renal cortical and medullary blood flows were measured using laser-Doppler flowmetry. Analysis of microdialyzed samples showed that the adenosine concentration in the renal medullary interstitial dialysate averaged 212 ± 5.2 nM, which was significantly higher than 55.6 ± 5.3 nM in the renal cortex ( n = 9). Renal medullary interstitial infusion of a selective A1antagonist, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX; 300 pmol ⋅ kg−1 ⋅ min−1, n = 8), did not alter renal blood flows, but increased urine flow by 37% and sodium excretion by 42%. In contrast, renal medullary infusion of the selective A2 receptor blocker 3,7-dimethyl-1-propargylxanthine (DMPX; 150 pmol ⋅ kg−1 ⋅ min−1, n = 9) decreased outer medullary blood flow (OMBF) by 28%, inner medullary blood flows (IMBF) by 21%, and sodium excretion by 35%. Renal medullary interstitial infusion of adenosine produced a dose-dependent increase in OMBF, IMBF, urine flow, and sodium excretion at doses from 3 to 300 pmol ⋅ kg−1 ⋅ min−1( n = 7). These effects of adenosine were markedly attenuated by the pretreatment of DMPX, but unaltered by DPCPX. Infusion of a selective A3receptor agonist, N 6-benzyl-5′-( N-ethylcarbonxamido)adenosine (300 pmol ⋅ kg−1 ⋅ min−1, n = 6) into the renal medulla had no effect on medullary blood flows or renal function. Glomerular filtration rate and arterial pressure were not changed by medullary infusion of any drugs. Our results indicate that endogenous medullary adenosine at physiological concentrations serves to dilate medullary vessels via A2 receptors, resulting in a natriuretic response that overrides the tubular A1 receptor-mediated antinatriuretic effects.

Role of Plasma Vasopressin in Changes of Water Balance Accompanying Acute Alcohol Intoxication

1995 ◽  
Vol 19 (3) ◽  
pp. 759-762 ◽  
Author(s):  
Hanna Taivainen ◽  
Kalevi Laitinen ◽  
Riitta Tahtela ◽  
Kalervo Kiianmaa ◽  
Matti J. Valimaki
Keyword(s):  
Water Balance ◽  
Alcohol Intoxication ◽  
Acute Alcohol Intoxication ◽  
Plasma Vasopressin

The Role of the ‘Walking Legs’ in Aquatic and Terrestrial Locomotion of the Crayfish Austropotamobius Pallipes (Lereboullet)

1975 ◽  
Vol 62 (2) ◽  
pp. 447-454 ◽  
Author(s):  
CAROLINE M. POND
Keyword(s):  
The Body ◽  
Hydrodynamic Drag ◽  
Terrestrial Locomotion ◽  
Austropotamobius Pallipes ◽  
The Third ◽  
Fourth Pair

1. The hydrodynamic drag acting on the crayfish Austropotamobius pallipes is measured and it is concluded that, in the range of velocities used in walking, the drag is independent of the posture of the limbs and the direction of motion of the body. At swimming velocities the streamlining caused by promotion of the legs reduces the drag losses to half that of a crayfish moving in the forwards walking posture at the same speed. 2. The forwards walking of intact crayfish is compared with that of the same animal after amputation of one or more pairs of legs. It is concluded that the third and fourth pair of legs provide most of the propulsion under water and the second pair is not essential to locomotion under any of the conditions tried.

Bora wind and heavy persistent precipitation: atmospheric water balance and role of air-sea fluxes over the Adriatic Sea

2017 ◽  
Vol 143 (703) ◽  
pp. 1165-1177 ◽  
Author(s):  
Silvio Davolio ◽  
Riccardo Henin ◽  
Paolo Stocchi ◽  
Andrea Buzzi
Keyword(s):  
Water Balance ◽  
Adriatic Sea ◽  
Atmospheric Water ◽  
Bora Wind

scholarly journals Critical role of PPARγ in water balance

2015 ◽  
Vol 47 (11) ◽  
pp. 538-540 ◽  
Author(s):  
Ningjun Li
Keyword(s):  
Water Balance ◽  
Critical Role

scholarly journals Contrasting pharmacological ETB receptor blockade with genetic ETB deficiency in renal responses to big ET-1

2001 ◽  
Vol 6 (1) ◽  
pp. 39-43 ◽  
Author(s):  
DAVID M. POLLOCK
Keyword(s):  
Renal Plasma Flow ◽  
Urine Flow ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Clearance Studies ◽  
Etb Receptor ◽  
Pharmacological Blockade ◽  
Series Of Experiments ◽  
Renal Responses

Renal clearance studies were conducted to determine the role of ETB receptors in the renal response to big endothelin-1 (big ET-1). Two series of experiments were conducted on Inactin-anesthetized rats to contrast acute pharmacological blockade of ETB receptors vs. genetic ETB receptor deficiency. In the first series, Sprague-Dawley rats were given either ETB-selective antagonist, A-192621, or vehicle (0.9% NaCl) prior to infusion of big ET-1 (10 pmol·kg−1·min−1) for 60 min. A-192621 significantly increased baseline mean arterial pressure (MAP; 102 ± 4 vs. 141 ± 6 mmHg, P < 0.05) and urine flow rate (0.5 ± 0.1 vs. 1.3 ± 0.2 μl/min, P < 0.05) without any effect on glomerular filtration rate (GFR) or effective renal plasma flow (ERPF). Big ET-1 significantly increased MAP in both groups but to a higher level in rats given antagonist (120 ± 6 vs. 169 ± 6 mmHg, P < 0.05). Big ET-1 increased urine flow in control rats but decreased in rats given antagonist. GFR and ERPF were decreased in rats given big ET-1, an effect that was exaggerated by ETB blockade. Another series of experiments examined the response to big ET-1 in rats lacking functional renal ETB receptors, known as spotting lethal ( sl) rats. Surprisingly, rats heterozygous ( sl/+) for ETB receptor deficiency had a significantly higher baseline MAP compared with homozygous ( sl/ sl) rats (134 ± 6 vs. 112 ± 7 mmHg, P < 0.05), although other variables were similar. Big ET-1 produced no significant change in MAP in either group. Urine flow, GFR, and ERPF were significantly decreased in both groups, although these changes were much larger in sl/ sl rats. These experiments indicate that the ETB receptor plays an important role in limiting the renal hemodynamic response to big ET-1. Furthermore, the diuretic actions of big ET-1 require a functional ETB receptor.

scholarly journals Event-Response Ellipses: A Method to Quantify and Compare the Role of Dynamic Storage at the Catchment Scale in Snowmelt-Dominated Systems

Water ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1824 ◽  
Author(s):  
Jessica Driscoll ◽  
Thomas Meixner ◽  
Noah Molotch ◽  
Ty Ferre ◽  
Mark Williams ◽  
...  
Keyword(s):  
Water Balance ◽  
Quantitative Relation ◽  
Catchment Scale ◽  
System A ◽  
Time Period ◽  
Ellipse Method ◽  
Streamflow Response ◽  
Dynamic Storage ◽  
Event Response

A method for quantifying the role of dynamic storage as a physical buffer between snowmelt and streamflow at the catchment scale is introduced in this paper. The method describes a quantitative relation between hydrologic events (e.g., snowmelt) and responses (e.g., streamflow) by generating event-response ellipses that can be used to (a) characterize and compare catchment-scale dynamic storage processes, and (b) assess the closure of the water balance. Event-response ellipses allow for the role of dynamic, short-term storage to be quantified and compared between seasons and between catchments. This method is presented as an idealization of the system: a time series of a snowmelt event as a portion of a sinusoidal wave function. The event function is then related to a response function, which is the original event function modified mathematically through phase and magnitude shifts to represent the streamflow response. The direct relation of these two functions creates an event-response ellipse with measurable characteristics (e.g., eccentricity, angle). The ellipse characteristics integrate the timing and magnitude difference between the hydrologic event and response to quantify physical buffering through dynamic storage. Next, method is applied to eleven snowmelt seasons in two well-instrumented headwater snowmelt-dominated catchments with known differences in storage capacities. Results show the time-period average daily values produce different event-response ellipse characteristics for the two catchments. Event-response ellipses were also generated for individual snowmelt seasons; however, these annual applications of the method show more scatter relative to the time period averaged values. The event-response ellipse method provides a method to compare and evaluate the connectivity between snowmelt and streamflow as well as assumptions of water balance.

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