Hemolymph Osmolality, Acid-Base Balance, and Ammonia Excretion of Penaeus japonicus Bate Exposed to Ambient Nitrite

1996 ◽  
Vol 30 (2) ◽  
pp. 151-155
Author(s):  
J.-C. Chen ◽  
S.-Y. Cheng
Keyword(s):  
Ammonia Excretion ◽  
Acid Base Balance ◽  
Acid Base ◽  
Penaeus Japonicus ◽  
Base Balance

Nitrogen excretion in germ-free and conventional chickens: effects of an alkali load

1978 ◽  
Vol 39 (1) ◽  
pp. 99-104 ◽  
Author(s):  
J. Okumura ◽  
D. Hewitt ◽  
Marie E. Coates
Keyword(s):  
Amino Acids ◽  
Uric Acid ◽  
Ammonia Excretion ◽  
Nitrogen Excretion ◽  
Acid Base Balance ◽  
Acid Base ◽  
Total N ◽  
Germ Free ◽  
Base Balance ◽  
Micro Organisms

1. Groups of three colostomized germ-free (GF) and conventional (CV) chickens aged 4 months were maintained for successive periods of 8 d on a diet containing 200 g casein/kg without and with sodium bicarbonate at the rate of 20 mmol/d and a nitrogen-free diet without and with NaHCO3at 9 mmol/d. Urine and faeces were collected during the last 3 d of each period.2. Total N, uric acid- and ammonia-N were determined in urine and total N in faeces. Amino acids were measured in hydrolysates of faeces collected during the periods when no NaHCO3was included in the diets.3. The CV birds excreted more N on the casein diets but less on the N-free diets than did their GF counterparts, the differences being mainly shown in the urine.4. On both diets hydrolysates of the faeces of CV birds contained smaller amounts of amino acids. On the N-free diet the proportions (g/160 g N) of serine, proline and threonine were reduced, suggesting some conservation of endogenous N by micro-organisms, and the proportions of histidine, alanine, lysine and methionine increased, possibly through microbial synthesis; on the casein diet, proportions of most amino acids were less, probably because bacterial deamination had occurred.5. Urinary excretion of total N, uric acid and ammonia was much greater on the casein than on the N-free diets. Inclusion of NaHCO3caused a sharp fall in urinary ammonia on both diets and in both environments.6. It was concluded that the level of dietary protein and the regulation of acid-base balance have more effect than microbial activity on the urinary ammonia excretion.

Renal regulation of acid-base balance in the bullfrog

1961 ◽  
Vol 201 (6) ◽  
pp. 980-986 ◽  
Author(s):  
Hisato Yoshimura ◽  
Masateru Yata ◽  
Minoru Yuasa ◽  
Robert A. Wolbach
Keyword(s):  
Carbonic Anhydrase ◽  
Ammonia Excretion ◽  
Respiratory Acidosis ◽  
Acid Base Balance ◽  
Acid Base ◽  
Urinary Ph ◽  
Base Balance ◽  
Chloride Excretion ◽  
Acid Load ◽  
Renal Carbonic Anhydrase

Renal mechanisms for the maintenance of acid-base balance were studied in the normal bullfrog, during metabolic and respiratory acidosis, and after carbonic anhydrase inhibition. Following intravenous administration of 0.3–12 mmole HCl/ kg, as 0.1 n HCl, urinary pH (initially pH 6.3–7.7) did not change significantly. However, urinary ammonia excretion increased more than twofold, and within 3–5 days the cumulative increase was equivalent to the acid load given. Despite the increased ammonia excretion, chloride excretion did not increase after acid loading. In both normal and acidotic bullfrogs ammonia excretion was correlated with an increase in urinary pH. Respiratory acidosis in the small frog, Rana limnocharis, produced by exposure to 6.4% CO2 in air, induced neither urinary acidification nor increased ammonia excretion; both urinary sodium and bicarbonate excretion increased. When renal carbonic anhydrase was inhibited by acetazoleamide injection, urine flow, sodium excretion, and bicarbonate excretion increased markedly, urinary pH increased slightly, and urinary ammonia excretion remained unchanged. These renal responses to acidosis are compared with those of the acidotic dog.

Sodium–hydrogen exchangers in the nematode Caenorhabditis elegans: investigations towards their potential role in hypodermal H+ excretion, Na+ uptake, and ammonia excretion, as well as acid–base balance

2017 ◽  
Vol 95 (9) ◽  
pp. 623-632 ◽  
Author(s):  
Aida Adlimoghaddam ◽  
Michael J. O’Donnell ◽  
Alex Quijada-Rodriguez ◽  
Dirk Weihrauch
Keyword(s):  
Caenorhabditis Elegans ◽  
Cell Volume Regulation ◽  
Ammonia Excretion ◽  
Transport Processes ◽  
Soil Nematode ◽  
Acid Base Balance ◽  
Nematode Caenorhabditis Elegans ◽  
Acid Base ◽  
C Elegans ◽  
Base Balance

Cation/proton exchangers of the cation proton antiporter 1 (CPA1) subfamily (NHEs, SLC 9) play an important role in many physiological processes, including cell volume regulation, acid–base homeostasis, and ammonia excretion. The soil nematode Caenorhabditis elegans (Maupas, 1900) (N2, 1968) expresses nine paralogues (NHX-1 to NHX-9). The current study was undertaken to investigate the role of the cation/proton exchanger in hypodermal Na+ and H+ fluxes, as well in ammonia excretion processes. Measurements using SIET (scanning ion-selective electrode technique) showed that the hypodermis promotes H+ secretion and Na+ uptake. Inhibitory effects on fluxes were observed upon application of amiloride but not EIPA, suggesting that NHXs are not involved in the transport processes. In response to stress induced by starvation or exposure to 1 mmol·L−1 NH4Cl, pH 5.5, or pH 8.0, body pH stayed fairly constant, with changes in mRNA expression levels detected in intestinal NHX-2 and hypodermal NHX-3. In conclusion, the study suggest that hypodermal apically localized EIPA-sensitive Na+/H+ exchangers do not likely play a role in ammonia excretion and Na+ uptake in the hypodermis of C. elegans, whereas apical amiloride-sensitive Na+ channels seem to be involved not just in hypodermal Na+ uptake but indirectly also in NH4+ and H+ excretion.

Use of a carbonic anhydrase Ca17a knockout to investigate mechanisms of ion uptake in zebrafish (Danio rerio)

2021 ◽  
Vol 320 (1) ◽  
pp. R55-R68
Author(s):  
Alex M. Zimmer ◽  
Milica Mandic ◽  
Hong Meng Yew ◽  
Emma Kunert ◽  
Yihang K. Pan ◽  
...  
Keyword(s):  
Carbonic Anhydrase ◽  
Danio Rerio ◽  
Ammonia Excretion ◽  
Ion Uptake ◽  
Whole Body ◽  
Acid Base Balance ◽  
Acid Base ◽  
Uptake Mechanism ◽  
Uptake Rates ◽  
Base Balance

In fishes, branchial cytosolic carbonic anhydrase (CA) plays an important role in ion and acid-base regulation. The Ca17a isoform in zebrafish ( Danio rerio) is expressed abundantly in Na+-absorbing/H+-secreting H+-ATPase-rich (HR) cells. The present study aimed to identify the role of Ca17a in ion and acid-base regulation across life stages using CRISPR/Cas9 gene editing. However, in preliminary experiments, we established that ca17a knockout is lethal with ca17a−/− mutants exhibiting a significant decrease in survival beginning at ∼12 days postfertilization (dpf) and with no individuals surviving past 19 dpf. Based on these findings, we hypothesized that ca17a−/− mutants would display alterations in ion and acid-base balance and that these physiological disturbances might underlie their early demise. Na+ uptake rates were significantly increased by up to 300% in homozygous mutants compared with wild-type individuals at 4 and 9 dpf; however, whole body Na+ content remained constant. While Cl− uptake was significantly reduced in ca17a−/− mutants, Cl− content was unaffected. Reduction of CA activity by Ca17a morpholino knockdown or ethoxzolamide treatments similarly reduced Cl− uptake, implicating Ca17a in the mechanism of Cl− uptake by larval zebrafish. H+ secretion, O2 consumption, CO2 excretion, and ammonia excretion were generally unaltered in ca17a−/− mutants. In conclusion, while the loss of Ca17a caused marked changes in ion uptake rates, providing strong evidence for a Ca17a-dependent Cl− uptake mechanism, the underlying causes of the lethality of this mutation in zebrafish remain unclear.

Branchial mechanisms of ion and acid–base regulation in the freshwater rainbow trout, Salmo gairdneri

1988 ◽  
Vol 66 (12) ◽  
pp. 2699-2708 ◽  
Author(s):  
D. G. McDonald ◽  
E. T. Prior
Keyword(s):  
Lactic Acid ◽  
Rainbow Trout ◽  
Sodium Bicarbonate ◽  
Ammonium Sulphate ◽  
Ammonia Excretion ◽  
Salmo Gairdneri ◽  
Acid Base Balance ◽  
Acid Base ◽  
Base Balance

Blood acid–base balance and branchial fluxes of Na+, Cl−, and acidic equivalents were examined in rainbow trout (Salmo gairdneri) in response to variations in external [NaCl] and following experimental acid or base loads (intravascular infusion of ammonium sulphate, lactic acid, or sodium bicarbonate). NaCl influx, NaCl efflux, and ammonia excretion covaried with external [NaCl]. Large fluxes of acidic equivalents across the gills were produced by infusion of both ammonium sulphate and sodium bicarbonate, but both treatments had little effect upon Na+ and Cl− uptake. We interpret this result as indicating that apical [Formula: see text] and [Formula: see text] exchange played little role in the branchial clearance of acidic equivalents. Instead, the results are consistent with the notion that acidic equivalents were excreted via diffusion through paracellular channels. A model is presented which suggests that the paracellular channels are the normal route for ionic efflux across the gills and that excretion of acidic equivalents results from modulation of the permselectivity of this pathway.

scholarly journals Defective bicarbonate reabsorption in Kir4.2 potassium channel deficient mice impairs acid-base balance and ammonia excretion

2020 ◽  
Vol 97 (2) ◽  
pp. 304-315 ◽  
Author(s):  
Yohan Bignon ◽  
Laurent Pinelli ◽  
Nadia Frachon ◽  
Olivier Lahuna ◽  
Lucile Figueres ◽  
...  
Keyword(s):  
Potassium Channel ◽  
Ammonia Excretion ◽  
Acid Base Balance ◽  
Acid Base ◽  
Bicarbonate Reabsorption ◽  
Base Balance ◽  
Deficient Mice

scholarly journals The Physiology of Dehydration Stress in the Land Crab, Cardisoma Carnifex: Respiration, Ionoregulation, Acid-Base Balance and Nitrogenous Waste Excretion

1986 ◽  
Vol 126 (1) ◽  
pp. 271-296 ◽  
Author(s):  
CHRIS M. WOOD ◽  
R. G. BOUTILIER ◽  
D. J. RANDALL
Keyword(s):  
Metabolic Alkalosis ◽  
Ammonia Excretion ◽  
French Polynesia ◽  
Strong Ion Difference ◽  
Acid Base Balance ◽  
Acid Base ◽  
Land Crab ◽  
Base Balance ◽  
Ion Shifts ◽  
Total Body

Air-breathing Cardisoma carnifex, collected in Moorea, French Polynesia, were held in fresh water similar in chemical composition to that in their burrows. Under control conditions, which allowed branchial chamber flushing but not ventilation of the medium, crabs demonstrated net Na+ and Cl− uptake, and ammonia, urea and base excretion (= acidic equivalent uptake). Throughout 192 h of water deprivation, crabs dehydrated slowly at a rate of 0.55 g H2O kg−1 h−1, eventually reaching a near lethal 18% loss of total body water. Increases in haemolymph osmolytes were quite variable (0–29%); electrolyte excretion was negligible. MOO2 and MCOCO2 both decreased by approximately 55%, maintaining an unusually low gas exchange ratio (R = 0.53), and suggesting general metabolic depression. There was no evidence of internal hypoxia as haemolymph lactate remained at hydrated levels and PaOO2 actually increased. The dominant acid-base response was a progressive metabolic alkalosis accompanied by a partially compensating rise in PaCOCO2. Alkalosis was probably caused by blockage of the normal aquatic excretion of base produced by the metabolism of this herbivore. Other possible causes were eliminated: i.e. alkalaemia due to contraction of the ECFV; entrainment via strong ion shifts; CaCO3 mobilization; and ammonia accumulation in the haemolymph. In the absence of water, net ammonia production and excretion both appeared to cease, and alternate end products (urea, uric acid) did not generally accumulate. Within 2h of rehydration, crabs regained more than half the lost water, MOO2 and MCOCO2 increased above control levels, and ammonia excretion and haemolymph concentration both exhibited a prolonged (56 h) 4- to 6-fold rise. At the same time, metabolic alkalosis was reversed in association with elevated net base excretion into the water; the latter was correlated with an increase in the strong ion difference (SID) flux ([Na+ + K+ + Ca2+ + Mg2+ - Cl−]). Note:

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