Quantification of presumptive Na+/H+ antiporters of the erythrocytes of trout and eel     

Scott D. Reid  Steve F. Perry 《Fish physiology and biochemistry》1994,12(6):455-463

The presumptive Na⁺/H⁺ exchange sites of trout and eel erythrocytes were quantified using amiloride-displaceable 5-(N-methyl-N-[³H]isobutyl)-amiloride (³H-MIA) equilibrium binding to further evaluate the mechanisms of i) hypoxia-mediated modifications in the trout erythrocyte -adrenergic signal transduction system and ii) the marked differences in the catecholamine responsiveness of this system between the trout and eel. MIA was a more potent inhibitor of both trout apparent erythrocyte proton extrusion (IC₅₀ = 20.1 ± 1.1 mol l^–1, N = 6) activity (as evaluated by measuring plasma pH changes after addition of catecholamine in vitro) and specific ³H-MIA binding (IC₅₀ = 257 ± 8.2 nmol l^–1, N = 3) than amiloride, which possessed a proton extrusion IC₅₀ of 26.1 ± 1.6 mol l^–1 (N = 6) and a binding IC₅₀ of 891 ± 113 nmol l^–1 (N = 3). The specific Na⁺ channel blocker phenamil was without effect on adrenergic proton extrusion activity or specific ³H-MIA binding. Trout erythrocytes suspended in Na⁺-free saline and maintained under normoxic conditions possessed 37,675 ± 6,678 (N = 6) amiloride-displaceable ³H-MIA binding sites per cell (B_max, presumptive Na⁺/H⁺ antiporters) with an apparent dissociation constant (K_D) of 244 ± 29 nmol l^–1 (N = 6). Acute hypoxia (PO₂ = 1.2 kPa; 30 min) did not affect the K_D, yet resulted in a 65% increase in the number of presumptive Na⁺/H⁺ antiporters. Normoxic eel erythrocytes, similarly suspended in Na⁺-free saline, possessed only 17,133 ± 3,716 presumptive Na⁺/H⁺ antiporters (N = 6), 45% of that of trout erythrocytes, with a similar K_D (246 ± 41 nmol l^–1, N = 6). These findings suggest that inter- and intra-specific differences in the responsiveness of the teleost erythrocyte -adrenergic signal transduction system can be explained, in part, by differences in the numbers of Na⁺/H⁺ exchange sites.  相似文献   

Origin identification of dried seaweed product “nori” by PCR–RFLP analysis of Pyropia yezoensis in the internal transcribed spacer ITS-1 region     

Ken Touhata  Atsushi Namikoshi  Tamami Suzuki  Jun Iguchi  Nanami Mizusawa  Tatsuro Hara  Shintaro Imamura  Takeshi Yabu  Yumiko Yamashita  Michiaki Yamashita 《Fisheries Science》2013,79(5):865-875

Nucleotide sequences in internal transcribed spacer (ITS)-1 region derived from dried nori products produced in Japan, China, and the Republic of Korea were compared. Thalli contained in the Japanese products were genetically homogenous, and their nucleotide sequences in ITS-1 were identical to those of the reference strains of Pyropia yezoensis f. narawaensis. In Chinese products, the thalli were related to P. yezoensis strain Minomiasakusa. In contrast, the thalli in the Korean products were genetically heterogeneous, and several different P. yezoensis strains and other Pyropia spp. were used for dried nori products. In some thalli produced in both China and Korea, the DNA sequences of the ITS-1 region were identical with that of Japan, suggesting that the cultivar strains might have been transplanted from Japan to China in recent years. The 432-bp-long nucleotide sequences in the ITS-1 region of thalli derived from Japanese origin were cleaved to two restriction fragments at 154 and 278 bp by cleavage of PCR-amplified products using MspI. Conversely, almost all of the corresponding sequences derived from China and Korea were lacking MspI or other restriction patterns, except for nori products from some areas that cultivate a closely related strain to the Japanese cultivar.  相似文献   

Phenotypic plasticity in gene expression and physiological response in red drum <Emphasis Type="Italic">Sciaenops ocellatus</Emphasis> exposed to a long-term freshwater environment     

Mariel Gullian Klanian  Omar Zapata Pérez  Miguel Angel Vela-Magaña 《Fish physiology and biochemistry》2018,44(1):73-85

Red drum (Sciaenops ocellatus) is a euryhaline fish commonly found in the Gulf of Mexico and along the Atlantic coast of North America. Because of high commercial demand and its euryhaline characteristics, aquaculture of this species has diversified from marine to low-salinity aquaculture systems. In recent years, interest in the feasibility of producing red drum in inland freshwater systems has grown and this prompted us to investigate its osmoregulatory capacity after rearing for 8 months in a freshwater aquaculture system. We compared the activities of several genes and enzymes involved in the osmoregulatory process in freshwater-acclimatized (FW) and seawater (SW) red drum. The gene expression profiles were variable: the expression of genes encoding Na⁺/K⁺-ATPase (NKA) and the cystic fibrosis transmembrane regulator (CFTR) was slightly higher in SW than FW fish, while phosphoenolpyruvate carboxykinase (PEPCK) and the glucocorticoid receptor messenger RNA (mRNA) levels were higher in FW red drum. The total plasma K concentration was 60.3% lower, and gill NKA activity was 63.5% lower in FW than in SW fish. PEPCK activity was twofold higher in FW than in SW red drum. Similarly, liver glycogen was 60% higher in FW fish. In summary, both gene expression and the enzyme activity data support the phenotypic plasticity of red drum and suggest that the limited capacity for ion homeostasis observed, in particular the low plasma K concentration, was due to the composition of freshwater and does not necessarily reflect a physiological inability to osmoregulate.  相似文献   

Primary sequence,tissue specificity and mRNA expression of the Na+,K+ -ATPase β1 subunit in the European eel (Anguilla anguilla)     

Christopher P. Cutler  Ian L. Sanders  Neil Hazon  Gordon Cramb 《Fish physiology and biochemistry》1995,14(5):423-429

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Comparison between parr and smolt Atlantic salmon (Salmo salar) α subunit gene expression of Na+/K+ ATPase in gill tissue     

Helena C. D'Cotta  Claudiane Gallais  Bénédicte Saulier  Patrick Prunet 《Fish physiology and biochemistry》1996,15(1):29-39

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pHi regulation and ultrastructural analysis in cultured gill cells from freshwater or seawater-adapted trout     

I. Leguen  M. Pisam  M. Bidet  M. Tauc  P. Poujeol 《Fish physiology and biochemistry》1998,18(3):297-309

Primary cultures of gill cells from freshwater and seawater-adapted trout were compared. These cultures, developed from an explant technique, exhibited a similar growth. Ultrastructural comparison between cultured and in situ cells showed that most of the cells in primary culture resembled the so called 'pavement' cells, whereas chloride cells were not observed in the cultured epithelium. Several other cells types, representing a minority of cells in primary culture, were observed (mucous cells, vesicolar cells, cells with large dense granules and cells containing lysosomes). Morphological observations of cultured pavement cells from freshwater and seawater trout gills were similar, although the density of cellular organelles in cells was less under freshwater conditions. In addition to the morphological comparison, the regulation of intracellular pH in cultured cells from freshwater and seawater gills was examined. Resting pHi was not different for freshwater or seawater gill cells. A sodium-dependent and amiloride-sensitive mechanism was found in cultured cells. Under the experimental conditions used here, this mechanism was most likely a Na⁺/H⁺ antiporter in pavement cells from freshwater and seawater-adapted trout. The comparison of pHi recovery after acidification of cells from freshwater and seawater gills showed that the activity or the number of antiporters was higher for cells from seawater trout gill.  相似文献   

Effects of adrenaline on ionic equilibria in red blood cells of rainbow trout (Salmo gairdneri)     

Thomas A. Heming  David J. Randall  Madeleine M. Mazeaud 《Fish physiology and biochemistry》1987,3(2):83-90

Effects of adrenaline on the equilibrium distributions of Na⁺ , K⁺ , H⁺ , Cl^– , and H₂O across the cell membrane of rainbow trout (Salmo gairdneri) erythrocytes were determinedin vitro, as a function of P CO₂ (1.76–7.77 torr). CO₂-carrying capacity of the blood was also examined. Plasma catecholamine concentrations inunanaesthetized, unrestrained trout were 3.1 nM adrenaline and 1.2 nM noradrenaline. Elevation of the plasma adrenaline concentrationin vitro to 4.6 × 10³ nM resulted in net gains of Na⁺ , Cl^– and H₂O by red cells, a net loss of H⁺ from red cells, and a pronounced red cell swelling. Adrenaline also reduced the CO₂-carrying capacity of trout bloodin vitro. The magnitudes of these effects increased with P_CO2 and, thus, were sensitive to blood HCO₃ ^– concentrations. The distribution of K⁺ between red cells and plasma was unaffected by adrenaline. Adrenergic-mediated ion movements and red cell swelling were sensitive to both propranolol and SITS. These results are consistent with the symport NaCl uptake model for adrenergic-mediated swelling of Baroinet al. (1984). The adrenergic response of fish erythrocytes may function to ameliorate the effects of blood acidoses on O₂-carrying capacity by maintaining red cell pH in the face of a decrease in plasma pH.  相似文献   

Proton pumps in the fish gill and kidney   总被引：2，自引：0，他引：2  

S.F. Perry  J.N. Fryer 《Fish physiology and biochemistry》1997,17(1-6):363-369

The proton pump or vacuolar type H⁺-ATPase is an oligomeric protein responsible for electrogenic H⁺ secretion in a variety of acid-secreting epithelia. Recently, the proton pump was identified in both the gill and kidney of freshwater-adapted rainbow trout (Oncorhynchus mykiss). Using immunocytochemistry, H⁺-ATPase has been localized in the pavement cells and chloride cells of the lamellar epithelium. During periods of internal acidosis, there is a marked increase in the expression of the branchial proton pump as identified by Western analysis, immunocytochemistry and in situ hybridization. This augmented expression of proton pumps occurs concomitantly with a marked increase in branchial acid excretion and Na⁺ uptake. Immunocytochemical studies suggest that the pavement cell, rather than the chloride cell, is the predominant site of acid excretion during periods of acidosis. These findings are consistent with the notion that in freshwater teleosts, Na⁺ uptake and H⁺ excretion are linked via the coupling of the electrogenic proton pump to apical membrane Na⁺ channels. This mechanism may be controlled by hormones including cortisol and/or growth hormone. The fish kidney plays an important role in regulating acidosis via the re-absorption of filtered HCO₃ ^-. Recently, we have demonstrated using Western analysis and immunocytochemistry, the presence of proton pump in rainbow trout kidney and observed increased H⁺-ATPase expression during respiratory acidosis. These new findings suggest a role for the renal proton pump in acid-base regulation.  相似文献   

β-adrenergic signal transduction in fish: interactive effects of catecholamines and cortisol     

Steve F. Perry  Scott D. Reid 《Fish physiology and biochemistry》1993,11(1-6):195-203

The elevation of plasma catecholamine levels during acute stress initiates a series of compensatory physiological and biochemical mechanisms to alleviate the disruptive effects of stress on blood oxygen transport. Of particular importance is the β-adrenergic activation of a Na⁺/H⁺ antiporter associated with the red blood cell (rbc) membrane. Upon activation, the Na⁺/H⁺ antiporter extrudes H⁺ from the rbc and the resultant alkalinization of the rbc interior serves to enhance both the affinity and the capacity of haemoglobin O₂ binding. The activation of the Na⁺/H⁺ exchanger is dependent upon the intracellular accumulation of cyclic AMP. The extent of cyclic AMP accumulation is determined, in part, by the number and/or affinities of cell surface β-adrenoreceptors. Recent studies have shown that the number of cell surface β-adrenoreceptors are rapidly increased during acute hypoxia and that this phenomenon may explain the enhanced responsiveness of hypoxic rbc's to exogenous catecholamines. In certain instances, plasma catecholamine and cortisol levels rise concurrently. We recently have shown that chronic (10 day) elevation of cortisol levels, in vivo, or short-term (24h) elevation, in vitro, caused significant elevation of internalized β-adrenoreceptors. Upon exposure of the rbc's to hypoxia, these additional receptors are rapidly recruited to the cell surface where they become functionally coupled to adenylate cyclase. Ultimately, therefore, chronic elevation of plasma cortisol levels increases the responsiveness of the rbc to circulating catecholamines. We recently have identified similar enhancement of cell surface β-adrenoreceptors by cortisol and increased physiological responsiveness (glycogenolysis) to catecholamines in trout hepatocytes. Thus, chronic elevation of cortisol levels appears to be generally adaptive for increasing the sensitivity of the β-adrenergic signal transduction system of at least two cell types (rbc's, hepatocytes) involved in the amelioration of acute stress when plasma catecholamine levels rise.

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Résumé L'élévation des niveaux de cathécolamines plasmatiques pendant un stress aigu déclenche une série de mécanismes physiologiques et biochimiques de compensation destinés à suprimer les effets destructeurs du stress sur les transport d'oxygène par le sang. L'activation β-adrénergique de l'antipore Na⁺/H⁺ associé à la membrane des globules rouges du sang (rbc) est particulièrement importante. Après activation, l'antipore Na⁺/H⁺ excrète du globule rouge H⁺ et l'alcalinisation du milieu intérieur du globule qui en résulte sert à stimuler l'affinité et la capacité de liaison hémoglobine-O₂. L'activation de l'échangeur Na⁺/H⁺ est dépendante de l'accumulation intracellulaire d'AMP cyclique. La quantité d'AMP cyclique accumulée est déterminée en partie par le nombre et/ou l'affinité des β-adrénorécepteurs situés à la surface des cellules. Des études récentes montrent que le nombre de β-adrénorécepteurs de surface augmente rapidement pendant une hypoxie aigue et que ce phénomène pourrait expliquer la stimulation de la réponse des globules rouges hypoxiques à des cathécolamines exogènes. Dans certains cas, les niveaux plasmatiques de cortisol et de cathécolamine augmentent simultanément. Nous avons récemment montré qu'une augmentation chronique (10 jours) des niveaux de cortisol in vivo ou une élévation de courte durée (24h) in vitro conduisent à une augmentation des β-adrénorécepteurs internalisés. Suite à l'exposition de globules rouges à une hypoxie, ces nouveaux récepteurs sont rapidement recrutés à la surface de la cellule où ils deviennent fonctionnellement couplés à l'adénylate cyclase. En dernier lieu donc, une élévation chronique des niveaux de cortisol augmente la réponse des globules rouges aux cathécolamines circulants. Nous avons récemment identifié une augmentation similaire des β-adrénorécepteurs de surface cellulaire par le cortisol et une réponse physiologique (glycogénolyse) stimulée par les cathécolamines dans les hépatocytes de truite. Ainsi, une élévation chronique des niveaux de cortisol semble être en général adaptative et augmentant la sensibilité du système de transduction du signal β-adrénergique dans au moins 2 types de cellules (les globules rouges et les hépatocytes) impliquées dans l'amélioration du stress aigu quand les niveaux de cathécolamine plasmatique augmentent.

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Characterization of transport Na+-ATPases in gills of freshwater tilapia     

Dr. Paul Balm  Nico Goossen  Sjef van de Rijke  Sjoerd Wendelaar Bonga 《Fish physiology and biochemistry》1988,5(1):31-38

Branchial plasma membranes from the freshwater cichlid teleostOreochromis mossambicus (tilapia) contain two Na⁺-dependent ATPases: Na⁺/K⁺ ATPase, and an amiloride-sensitive ATPase which is postulated to operate as a Na⁺/H⁺ (–NH₄ ⁺) ATPase. It is suggested that both enzyme activities are located in the basolateral membrane system of the chloride cells. K⁺ has opposing effects on the two enzymes: it stimulates Na⁺/K⁺ ATPase and inhibits Na⁺/H⁺ (–NH₄ ⁺) ATPase activity. Na⁺/H⁺ ATPase appears more sensitive to NH₄ ⁺ at low concentrations than Na⁺/K⁺ ATPase and the stimulatory effect by NH₄ ⁺ ions on the first enzyme could be important in facilitating NH₄ ⁺ excretion by tilapia gills under physiological conditions.In vitro maximum stimulation by NH₄ ⁺ is similar for the two enzymes (200%). In contrast to Na⁺/K⁺ ATPase, Na⁺/H⁺ ATPase activity is inhibited by supra-physiological (>20 mM) concentrations of NH₄ ⁺.  相似文献   

Cloning and molecular characterization of cationic amino acid transporter y+LAT1 in grass carp (Ctenopharyngodon idellus)     

Jixuan Yang  Qingsong Tan  Wenhuan Zhu  Chen Chen  Xufang Liang  Lei Pan 《Fish physiology and biochemistry》2014,40(1):93-104

The solute carrier family 7A, member 7 gene encodes the light chain- y⁺L amino acid transporter-1 (y⁺LAT1) of the heterodimeric carrier responsible for cationic amino acid (CAA) transport across the basolateral membranes of epithelial cells in intestine and kidney. Rising attention has been given to y⁺LAT1 involved in CAA metabolic pathways and growth control. The molecular characterization and function analysis of y⁺LAT1 in grass carp (Ctenopharyngodon idellus) is currently unknown. In the present study, full-length cDNA (2,688 bp), which encodes y⁺LAT1 and contains a 5′-untranslated region (319 bp), an open reading frame (1,506 bp) and a 3′-untranslated region (863 bp), has been cloned from grass carp. Amino acid sequence of grass carp y⁺LAT1 contains 11 transmembrane domains and shows 95 %, 80 % and 75 % sequence similarity to zebra fish, amphibian and mammalian y⁺LAT1, respectively. The tissue distribution and expression regulation by fasting of y⁺LAT1 mRNA were analyzed using real-time PCR. Our results showed that y⁺LAT1 mRNA was highly expressed in midgut, foregut and spleen while weakly expressed in hindgut, kidney, gill, brain, heart, liver and muscle. Nutritional status significantly influenced y⁺LAT1 mRNA expression in fish tissues, such as down-regulation of y⁺LAT1 mRNA expression after fasting (14 days).  相似文献   

中国明对虾NHE3基因克隆及其在pH胁迫下的表达   总被引：1，自引：1，他引：0  

李政道  李健  葛倩倩  王佳佳  何玉英  王培春 《中国水产科学》2018,25(5):958-966

为研究钠/氢交换体(Na+/H+-exchanger,NHE)在中国明对虾(Fenneropenaeus chinensis)响应pH胁迫过程中发挥的作用,首先采用静水毒性实验方法确定了中国明对虾酸碱半致死pH,然后利用RACE技术克隆了中国明对虾Na+/H+-exchanger isoform 3(命名为FcNHE3)基因,并通过荧光定量PCR及RNA干扰技术分析了其在pH胁迫下的表达特征及功能。结果显示,72 h酸性半致死pH和碱性半致死pH分别为5.2和9.1。克隆获得FcNHE3基因(Gen Bank:MF373587)cDNA序列全长3508 bp,开放阅读框2805 bp,编码934个氨基酸,具有信号肽和12个跨膜结构域;蛋白同源分析发现,FcNHE3与青蟹(Carcinus maenas)同源性最高,达到74%;系统进化分析显示,FcNHE3与三疣梭子蟹(Portunus trituberculatus)和青蟹亲缘关系最近。荧光定量PCR分析表明,FcNHE3基因在鳃组织中表达量显著高于其他组织(P0.05);酸性半致死pH(pH 5.2)胁迫下,FcNHE3基因在整个胁迫过程中显著上调表达(P0.05);碱性半致死pH(pH 9.1)胁迫下,FcNHE3基因在前48 h显著下调表达(P0.05),12 h表达量最低,仅在72 h出现上调表达。RNA干扰后,FcNHE3基因表达受到抑制,pH 5.2胁迫下对虾存活率相比对照组显著下降。研究表明相较于高pH胁迫,FcNHE3基因在中国明对虾响应低pH胁迫过程中可能发挥更重要的调节作用。  相似文献   

Exploration of the mechanisms of protein quality control and osmoregulation in gills of Chromis viridis in response to reduced salinity     

Cheng-Hao Tang  Ming-Yih Leu  Wen-Kai Yang  Shu-Chuan Tsai 《Fish physiology and biochemistry》2014,40(5):1533-1546

Fish gills are the vital multifunctional organ in direct contact with external environment. Therefore, activation of the cytoprotective mechanisms to maintain branchial cell viability is important for fish upon stresses. Salinity is one of the major factors strongly affecting cellular and organismal functions. Reduction of ambient salinity may occur in coral reef and leads to osmotic stress for reef-associated stenohaline fish. However, the physiological responses to salinity stress in reef-associated fish were not examined substantially. With this regard, the physiological parameters and the responses of protein quality control (PQC) and osmoregulatory mechanisms in gills of seawater (SW; 33–35 ‰)- and brackish water (BW; 20 ‰)-acclimated blue-green damselfish (Chromis viridis) were explored. The results showed that the examined physiological parameters were maintained within certain physiological ranges in C. viridis acclimated to different salinities. In PQC mechanism, expression of heat-shock protein (HSP) 90, 70, and 60 elevated in response to BW acclimation while the levels of ubiquitin-conjugated proteins were similar between the two groups. Thus, it was presumed that upregulation of HSPs was sufficient to prevent the accumulation of aggregated proteins for maintaining the protein quality and viability of gill cells when C. viridis were acclimated to BW. Moreover, gill Na⁺/K⁺-ATPase expression and protein amounts of basolaterally located Na⁺/K⁺/2Cl^? cotransporter were higher in SW fish than in BW fish. Taken together, this study showed that the cytoprotective and osmoregulatory mechanisms of blue-green damselfish were functionally activated and modulated to withstand the challenge of reduction in salinity for maintaining physiological homeostasis.  相似文献   

Biochemical and molecular differences in diploid and triploid ocean-type chinook salmon (<Emphasis Type="Italic">Oncorhynchus tshawytscha</Emphasis>) smolts     

J. Mark Shrimpton  Aurora M. C. Sentlinger  John W. Heath  Robert H. Devlin  Daniel D. Heath 《Fish physiology and biochemistry》2007,33(3):259-268

There is increasing evidence for complex dosage effects on gene expression, enzyme activity and phenotype resulting from induced ploidy change. In this study, ocean-type chinook salmon were bred using a 2 × 2 factorial mating design to create four families and test whether triploidization resulted in changes in growth performance and smolting. Eggs were pressure shocked after fertilization to create triploid fish from a subset of each family. In June, fish were sampled for size, plasma insulin-like growth factor 1 (IGF-1), gill Na⁺–K⁺-ATPase activity, and expression of two Na⁺–K⁺-ATPase α subunits in the gill. Diploids were significantly heavier than triploids, and there were significant differences due to family. Despite a significant positive correlation between plasma IGF-1 and fish size, plasma IGF-1 did not differ between diploid and triploid smolts. Diploids also had significantly greater gill Na⁺–K⁺-ATPase enzyme activities than triploids and there was a strong family effect. Gill Na⁺–K⁺-ATPase α1b isoform expression differed significantly by family, but not ploidy, and generally families with lower Na⁺–K⁺-ATPase enzyme activity had higher α1b isoform gene expression. Na⁺–K⁺-ATPase α1a isoform expression did not differ among any of the groups. Although diploids were larger and had higher specific activities of Na⁺–K⁺-ATPase in the gills, there was no difference in gene expression or circulating hormone levels. The strong family effect, however, suggests that strain selection may be useful in improving performance of triploids for aquaculture.  相似文献   

Fish anesthesia: effects of the essential oils of Hesperozygis ringens and Lippia alba on the biochemistry and physiology of silver catfish (Rhamdia quelen)     

Cândida Toni  Alexssandro Geferson Becker  Larissa Novaes Simões  Carlos Garrido Pinheiro  Lenise de Lima Silva  Berta Maria Heinzmann  Braulio Otomar Caron  Bernardo Baldisserotto 《Fish physiology and biochemistry》2014,40(3):701-714

The anesthetic activities of the essential oils (EOs) of Hesperozygis ringens (EOHR) and Lippia alba (EOLA) and their effects in silver catfish (Rhamdia quelen) after anesthesia and recovery were investigated. Fish (32.19 ± 1.24 g) were submitted to one of the following treatments for each EO: basal group, control, or anesthesia (150, 300, or 450 μL L^?1 EO). After that the anesthesia was induced or simulated and the biometric measurements were completed, fish were transferred to anesthetic-free aquaria to allow for recovery. Fish were sampled at 0, 15, 30, 60, and 240 min after recovery. At time 0 of recovery, the ventilatory rate was lower in the groups anesthetized with either EO. In comparison with the basal group, control fish showed an increase in plasma glucose, aspartate aminotransferase (AST), and Na⁺ levels and a reduction in Na⁺/K⁺-ATPase activity at 0 min of recovery. Plasma levels of ammonia and Na⁺ were lower in the fish anesthetized with EOLA (450 μL L^?1) and EOHR (all concentrations), respectively, than in the control fish. Additionally, lactate, AST, alanine aminotransferase, K⁺ plasma levels, and gill Na⁺/K⁺-ATPase and H⁺-ATPase activities were higher in the fish anesthetized with either EOHR or EOLA than in the control fish. The EOs promoted slight changes in silver catfish that enabled both an adaptive response and the recovery of most of the measured parameters after 240 min regardless of concentration or EO that was used. These findings support the use of EOHR and EOLA as anesthetics for fish.  相似文献   

Molecular characterization and expression analysis of AMPK α subunit isoform genes from <Emphasis Type="Italic">Scophthalmus maximus</Emphasis> responding to salinity stress     

Lin Zeng  Bin Liu  Chang-Wen Wu  Ji-Lin Lei  Mei-Ying Xu  Ai-Yi Zhu  Jian-She Zhang  Wan-Shu Hong 《Fish physiology and biochemistry》2016,42(6):1595-1607

AMP-activated protein kinase (AMPK) is a highly conserved and multi-functional protein kinase that plays important roles in both intracellular energy balance and cellular stress response. In the present study, molecular characterization, tissue distribution and gene expression levels of the AMPK α1 and α2 genes from turbot (Scophthalmus maximus) under salinity stress are described. The complete coding regions of the AMPK α1 and α2 genes were isolated from turbot through degenerate primers in combination with RACE using muscle cDNA. The complete coding regions of AMPK α1 (1722 bp) and α2 (1674 bp) encoded 573 and 557 amino acids peptides, respectively. Multiple alignments, structural analysis and phylogenetic tree construction indicated that S. maximus AMPK α1 and α2 shared a high amino acid identity with other species, especially fish. AMPK α1 and α2 genes could be detected in all tested tissues, indicating that they are constitutively expressed. Salinity challenges significantly altered the gene expression levels of AMPK α1 and α2 mRNA in a salinity- and time-dependent manners in S. maximus gill tissues, suggesting that AMPK α1 and α2 played important roles in mediating the salinity stress in S. maximus. The expression levels of AMPK α1 and α2 mRNA were a positive correlation with gill Na⁺, K⁺-ATPase activities. These findings will aid our understanding of the molecular mechanism of juvenile turbot in response to environmental salinity changes.  相似文献   

Gill ATPase activities of silver perch, Bidyanus bidyanus (Mitchell), and golden perch, Macquaria ambigua (Richardson): Effects of environmental salt and ammonia     

Mostafa Alam 《Aquaculture (Amsterdam, Netherlands)》2006,251(1):118-133

The Australian freshwater fish, silver and golden perch, are increasingly being used for aquaculture. Addition of salt to water is commonly used in commercial aquaculture to reduce stress attributed to high ammonia concentrations. The activities in gill homogenates of ouabain-sensitive Na⁺/K⁺-ATPase and NEM-sensitive ATPases (as a measure of H⁺-ATPases) of silver and golden perch were measured after maintaining the fish in water containing different salt and ammonia concentrations. Six treatments were applied in a 2 × 3 factorial design: two salt treatments, low salt (LS) of 2.5 g l^− 1 and high salt (HS) 5 g l^− 1, and three ammonia treatments, no added ammonia (NA), low ammonia (LA), 3 mg total ammonia nitrogen (TAN) l^− 1 and high ammonia (HA), 5 mg TAN l^− 1. In both species, activity of Na⁺/K⁺-ATPase was lowest in fish kept in the LSNA treatment (7.4 ± 0.4 μmol Pi mg protein^− 1 h^− 1 for silver perch and 3.1 ± 0.6 for golden perch) and highest in the HSHA treatment (15.2 ± 1.0 μmol Pi mg^− 1 protein h^− 1 for silver and 8.4 ± 1.2 for golden perch). In both species there was a significant increase (P < 0.001) in Na⁺/K⁺-ATPase activity with increase in salt concentration and with an increase in ammonia concentrations. A significant interaction (P < 0.036) between salt and ammonia on Na⁺/K⁺-ATPase activity was observed in silver but not in golden perch. In contrast, the lowest activity for NEM-sensitive ATPase was observed in the HSNA treatment (1.0 ± 0.2 μmol Pi mg^− 1 protein h^− 1 for silver and 1.5 ± 0.4 for golden perch) and highest in LSHA treatment (2.9 ± 0.4 μmol Pi mg^− 1 protein h^− 1 for silver and 3.6 ± 1.2 for golden perch). In both species there was a significant decrease in NEM-sensitive ATPase activity with increase in salt concentration and an increase in activity with increase in ammonia (P < 0.003). In silver perch, a significant interaction between the treatments was observed (P < 0.02). The results suggest that in these species of freshwater fish the Na⁺/K⁺-ATPase has a role in salt and ammonia homeostasis and that the NEM-sensitive ATPases are more active in fish kept in water with a lower salt content. It is possible that the increase in ammonia resistance when salt is added to the environmental water in commercial aquaculture systems may be due to the effects of salt on gill Na⁺/K⁺-ATPase activity rather than the NEM-sensitive ATPases.  相似文献   

Lead accumulation and its effects on the branchial physiology of Prochilodus lineatus     

Andrea Martini Ribeiro  Wagner Ezequiel Risso  Marisa Narciso Fernandes  Claudia B. R. Martinez 《Fish physiology and biochemistry》2014,40(3):645-657

The purpose of this work was to determine the tissue accumulation of lead (Pb) and its effects on osmoregulatory processes of the freshwater fish Prochilodus lineatus. Juvenile fish were exposed to Pb (from 1.7 to 0.7 mg of dissolved Pb L^?1) for 6, 24 and 96 h and Pb accumulation was analyzed in the gills, liver, kidneys, blood cells and muscle. The following parameters were also analyzed: hematologic (hemoglobin content, hematocrit and number of red blood cells), metabolic (blood glucose), endocrine (blood cortisol), osmo ionic (plasma osmolality and Na⁺, K⁺, Cl^? and Ca⁺² concentrations), gill enzymes (Na⁺/K⁺-ATPase and carbonic anhydrase), chloride cell (CC) density and CC location in the gills. Pb accumulated in all the analyzed tissues, with the kidneys showing the highest concentration, followed by the gills and liver. The lowest Pb concentrations were found in blood cells and muscle. Pb promoted an increase in blood glucose after 6 and 24 h exposure. Gill Na⁺/K⁺-ATPase was inhibited after 24 h of exposure, but its activity was restored at 96 h, probably due to the increase in CC in gill lamellae. Plasma Na⁺ was reduced after 6 and 96 h, while K⁺ concentrations increased at all the experimental times. Fish exposed to Pb showed reduced plasma Ca⁺² at all experimental periods. Hematologic parameters remained unchanged. Overall, this study demonstrated that Pb interferes in osmoregulatory processes of P. lineatus and the proliferation of CC in the gills is a response in order to reestablish adequate ion concentrations.  相似文献   

Salinity changes in the anadromous river pufferfish,Takifugu obscurus,mediate gene regulation   总被引：1，自引：0，他引：1  

Su-Young Jeong  Jin-Hyoung Kim  Wan-Ok Lee  Hans-Uwe Dahms  Kyung-Nam Han 《Fish physiology and biochemistry》2014,40(1):205-219

This study aimed to better understand the hydromineral regulatory response of the anadromous river pufferfish, Takifugu obscurus, to salinity changes through real-time RT-PCR. After abrupt transfer from 30 or 5 psu to 5 or 30 psu, respectively, we analyzed the mRNA expression of Na⁺/K⁺ ATPase, prolactin receptor, and aquaporin from osmoregulatory organs of the river pufferfish such as gills, kidney, and intestine. Na⁺/K⁺ ATPase showed notable changes in the gills and kidney when salinity was increased. In the gills, the expression level of Na⁺/K⁺ ATPase suddenly increased within a day after abrupt transfer from 5 to 30 psu and then slightly declined within 2 days after exposure. In the kidney, Na⁺/K⁺ ATPase has shown consistently high mRNA expression after the increase in salinity. Expression levels of the prolactin receptor gene increased when environmental salinity decreased. In the intestine, gene expression of the prolactin receptor remained high, even when salinity decreased. To the contrary, there was a steady increase or decrease in mRNA expression in the kidney in response to salinity decrease or increase, respectively. As for aquaporins, aquaporin 1 was mainly expressed in the intestine and kidney, and aquaporin 3 was mainly expressed in the gills and intestine. In the gills, increased expression of aquaporin 3 was found after transfer to lower salinity and in the intestine and kidney, a decrease in salinity followed by an abrupt decrease in aquaporin 1 and aquaporin 3. Contrastingly, the expression of these genes increased in the intestine after transfer to 30 psu. Osmoregulatory genes were expressed in diverse organs, apparently to overcome an influx or exhaust of water or ions. A superior adaptation ability of the river pufferfish to a wide range of salinities is most reasonably due to active osmoregulatory processes mediated by the genes monitored here.  相似文献   

The role of Ca2+ and Na+ membrane transport in brook trout (Salvelinus fontinalis) spermatozoa motility   总被引：1，自引：0，他引：1  

Olga Bondarenko  Borys Dzyuba  Jacky Cosson  Marek Rodina  Otomar Linhart 《Fish physiology and biochemistry》2014,40(5):1417-1421

The role of environmental ion composition and osmolality in Ca²⁺ signaled activation was assessed in spermatozoa of brook trout Salvelinus fontinalis. Milt from ten mature males was obtained by abdominal massage. Spermatozoa motility was evaluated in 0, 100, and 300 mOsm/kg NaCl or sucrose solutions, buffered by 10 mM Tris–HCl pH 8.5. For investigation of spermatozoa reaction to external Ca²⁺ concentration, 2 mM ethylene glycol tetraacetic acid (EGTA) was added to the activation media as a calcium ions chelator. For investigation of the effect of external Na⁺ concentration in conditions of low external Ca²⁺, 100 µM amiloride was added to the EGTA-containing solutions as a Na⁺ transport blocker. Low motility was observed in sucrose (Na⁺ free) solutions containing 2 mM EGTA but not in Na⁺ solutions containing 2 mM EGTA. Addition of amiloride led to significantly increased motility (P < 0.05) compared with sucrose (Na⁺ free) solutions containing 2 mM EGTA. We conclude that Na⁺ transport in Ca²⁺-free solutions plays a regulatory role in brook trout spermatozoa activation. The influence of competitive Na⁺ and Ca²⁺ transport on the control of spermatozoa activation requires further study with respect to its application for improvement of artificial activation and storage media.  相似文献