|
|
|
| Registros recuperados: 45 | |
|
| |
|
| |
|
| |
|
|
| Amaral,Marcelo da Cunha; Bonecker,Ana Cristina Teixeira; Ortiz,Cláudio H. D.. |
| This work aimed to know the tolerance mechanisms through the salinity variation by Na+ K+ - ATPase and Mg++ - ATPase and enzymes encountered in the gills of Poecilia vivipara. In field, the presence of this species was observed in salinities of 0 and 28. In laboratory, these fish were maintained in aquarium with mean salinity of 30 and positive responses were obtained. Some adult specimens, collected in a lagoon of the Coqueiros Beach, were utilized as matrixes. In the experiments the specimens used were those born in the test aquarium. For each salinity studied three replicates were made with three specimens for each one. The alevins were maintained in salinities of 5, 10, 15, 20, 25, 30 and 35 during a month for adaptation. Gills were extracted in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Poecilia vivipara; Na+ K+ ATPase; Mg++ ATPase; Osmoregulation. |
| Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132001000100001 |
| |
|
|
| SABAT,PABLO; FARIÑA,JOSÉ M.; SOTO-GAMBOA,MAURICIO. |
| Feeding on saline marine foods may be especially challenging for passerine birds that lack functional salt glands and have a limited ability to concentrate urine. To reduce the salt load imposed by consumption of marine food these birds may select food with low salt contents and/or increase their intake of freshwater. The genus Cinclodes is particular among passerines because it includes species that inhabit both inland and maritime shores. We analyzed the diet of Cinclodes nigrofumosus and explored the possible relationships between dietary composition and salt load at mesic and arid coastal sites of Chile. From a biogeographical perspective, we hypothesized that freshwater availability is critical to the relationship between diet composition and osmotic... |
| Tipo: Journal article |
Palavras-chave: Cinclodes; Dietary habits; Osmoregulation; Osmotic load. |
| Ano: 2003 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2003000200017 |
| |
|
|
| De Wachter, B.; Gillikin, D.P.; Tack, J.. |
| The potential long-term effects of altered salinity regimes on the bioenergetics of two ecologically important Kenyan mangrove crabs, Neosarmatium meinerti de Man, 1887 and Neosarmatium smithi H. Milne Edwards, 1853 were investigated in light of recent findings suggesting that groundwater redirection may alter salinity regimes in Kenyan mangroves. Although changes in groundwater may cause only small increases in salinities, these changes would be chronic and may impact crab populations already living above their optimal salinity. To assess potential impacts, fundamental physiological processes and hemolymph components were measured on animals acclimated to 16‰, 32‰, 48‰ and 65‰ for 4 weeks in a field laboratory. For comparative purposes, crabs were also... |
| Tipo: Journal Contribution |
Palavras-chave: Ecophysiology; Salinity Tolerance; Energy Budget; Osmoregulation; Sesarmidae; Crab fisheries. |
| Ano: 2004 |
URL: http://hdl.handle.net/1834/693 |
| |
|
| |
|
|
| SABAT,PABLO; NESPOLO,ROBERTO F; BOZINOVIC,FRANCISCO. |
| Birds living in desert environments have been the preferred models for the study of physiological adaptations to water scarcity. Passerine birds living in marine coastal habitats face similar problems, yet physiological adaptations to water conservation in such species have been poorly documented. We measured total evaporative water loss (TEWL) and rates of oxygen consumption (VO2) in three species of passerine birds dwelling in marine and fresh water habitats. Mass specific total evaporative water loss was significantly lower in the marine species, Cinclodes nigrofumosus, than in species inhabiting areas near freshwater sources. We found a positive relationship between TEWL and VO2. The ratio of TEWL to VO2 (relative evaporative water loss, RTEWL) showed... |
| Tipo: Journal article |
Palavras-chave: Evaporative water loss; Cinclodes; Osmoregulation; Passerines; Salt. |
| Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2004000200001 |
| |
|
|
| Azevedo Neto,André Dias de; Prisco,José Tarquinio; Enéas-Filho,Joaquim; Lacerda,Claudivan Feitosa de; Silva,José Vieira; Costa,Paulo Henrique Alves da; Gomes-Filho,Enéas. |
| Seeds from eight different maize genotypes (BR3123, BR5004, BR5011, BR5026, BR5033, CMS50, D766 and ICI8447) were sown in vermiculite, and after germination they were transplanted into nutrient solution or nutrient solution containing 100 mmol.L-1 of NaCl and placed in a greenhouse. During the experimental period plant growth (dry matter, shoot to root dry mass ratio, leaf area, relative growth rate, and net assimilation rate), leaf temperature, stomatal conductance, transpiration, predawn water potential, sodium, potassium, soluble amino acids and soluble carbohydrate contents were determined in both control and salt stressed plants of all genotypes studied. Salt stress reduced plant growth of all genotypes but the genotypes BR5033 and BR5011 were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Growth analysis; Osmoregulation; Salinity; Transpiration; Zea mays; Water relations. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-04202004000100005 |
| |
|
|
| Mugnier, Chantal; Soyez, Claude. |
| The effect of different levels of dissolved oxygen (DO) and a decreased temperature combined with severe hypoxia were studied in the blue shrimp Litopenaeus stylirostris in relation to molt stage. In the first experiment, shrimps were submitted to DO concentrations of 5 to 1 mg l(-1). Osmoregulatory capacity (OC) was measured in shrimps at molt stage C after 6, 24, or 48 h of exposure. No mortality was recorded but a significant negative effect of DO concentration on hypo-OC was observed for DO concentrations below 3 mg l(-1). Osmoregulation improved after 48 h exposure, compared to 6 and 24 h exposure. In a second experiment, temperature was decreased from 28 to 22 degreesC in 24 h, before a severe hypoxia of 0.5+/-0.1 mg O-2 l(-1) was applied.... |
| Tipo: Text |
Palavras-chave: Temperature; Stress; Penaeid shrimp; Osmoregulation; Molt stage; Litopenaeus stylirostris; Hypoxia. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-372.pdf |
| |
|
|
| SABAT,PABLO; MARTÍNEZ DEL RÍO,CARLOS. |
| Passerines lack functional salt glands and to a large extent avoid feeding on marine invertebrates. An exception is Cinclodes nigrofumosus. Previous studies reported that the contents of its gastrointestinal tract had a lower osmolality than seawater suggesting that birds were supplementing their marine invertebrate diet with terrestrial invertebrates and fresh water at certain periods of the year. We report seasonal changes in the diet of C. nigrofumosus at two contrasting coastal localities in Central Chile and document the potential correlation between weather and feeding habits with osmoregulatory features in this species. We expected that C. nigrofumosus would increase its use of osmotically challenging marine dietary sources when fresh water is... |
| Tipo: Journal article |
Palavras-chave: Cinclodes; Isotopes; Renal function; Osmoregulation; Seasonal changes. |
| Ano: 2005 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2005000200009 |
| |
|
|
| Boutet, Isabelle; Ky, Chin Long; Bonhomme, Francois. |
| Euryhaline teleosts possess the capacity to osmoregulate under various environmental conditions (freshwater to hypersaline water). This physiological capacity is generally monitored using enzyme activity assays (Na+/K+-ATPase...), hormones quantification (prolactine, growth hormone) or their mRNAs expression. To date, few studies addressed the genetic correlates of adaptation to varying salinity at a molecular level in such fish. In the sea bass Dicentrarchus labrax, genetic differentiation was observed at specific allozyme loci between lagoon- and open-sea populations. In the present study, we investigated transcriptomic response of D. labrax to salt- and freshwater acclimation in two organs involved in osmoregulation, gill and intestine. By using... |
| Tipo: Text |
Palavras-chave: Suppression subtractive hybridisation; Carbonic anhydrase; Osmoregulation; MRNA expression; Sea bass. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1901.pdf |
| |
|
|
| Lorin, N; Boulo, Viviane; Bodinier, C; Charmantier, G. |
| This study combines a cellular and molecular analysis of the Na+/K+/2Cl(-) cotransporter (NKCC) to determine the osmoregulatory role of this protein in different tissues during the ontogeny of the sea bass. We have characterized the complete sequence of the NKCC1 isoform isolated from the sea bass gills and have identified, by immunofluorescence, NKCC1, and other isoforms, within the epithelium of the major osmoregulatory organs. Different (absorptive and secretory) functions have been attributed to this protein according to the tissue and salinity. The effects of short- (1-4 days), medium- (7-21 days) and long (6 months)-term freshwater (FW) adaptations were investigated, in comparison with seawater (SW)-maintained sea bass. In adult sea bass after... |
| Tipo: Text |
Palavras-chave: Quantitative expression; Immunofluorescence; Osmoregulation; Ontogeny; Dicentrarchus labrax; Na+/K+/2Cl( ) cotransporter. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-3531.pdf |
| |
|
|
| Giffard, I; Charmantier, G; Grousset, E; Aujoulat, F; Castille, R. |
| The ontogeny of the digestive tract (DT) and of Na+/K+-ATPase localization was investigated during the early postembryonic development (from yolk sac larva to juvenile) of the euryhaline teleost Dicentrarchus labrax reared at two salinities: seawater and diluted seawater. Histology, electron microscopy and immunocytochemistry were used to determine the presence and differentiation of ion transporting cells. At hatching, the DT is an undifferentiated straight tube over the yolk sac. At the mouth opening (day 5), it comprises six segments: buccopharynx, esophagus, stomach, anterior intestine, posterior intestine and rectum, well differentiated at the juvenile stage (day 72). The enterocytes displayed ultrastructural features similar to those of... |
| Tipo: Text |
Palavras-chave: Osmoregulation; Na+/K+ ATPase; Immunolocalization; Fish larva; Enteric ionocyte. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-4653.pdf |
| |
|
|
| Rosso,Felipe Link de; Bolner,Keidi C. S.; Baldisserotto,Bernardo. |
| Low dissolved oxygen levels in the water (hypoxia) can be provoked by oxygen consumption by fish and other organisms, organic matter decomposition, phytoplankton blooms, and temperature increase. The objective of the present study was to investigate Na+, Cl-, K+, and ammonia fluxes in silver catfish (Rhamdia quelen) exposed to different dissolved oxygen levels. Juveniles (9 ± 1g) maintained at 6.0 mg.L-1 dissolved oxygen were transferred to four 40 L aquaria with different dissolved oxygen levels (in mg.L-1): 6.0, 4.5, 3.5, and 2.5. In another series of experiments, juveniles were acclimated at 6.0 or 2.5 mg.L-1 dissolved oxygen levels, and then placed in two 40 L aquaria with 6.0 mg.L-1 dissolved oxygen. For both series of experiments, 1, 24, 48 or 120 h... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Oxygen saturation; Osmoregulation; Jundiá. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252006000400007 |
| |
|
| |
|
|
| ALDEA,PATRICIA; SABAT,PABLO. |
| We studied the osmoregulatory responses of the granivore Zonotrichia capensis, acclimated to high- and low-protein diets as well as two levels of water intake. We tested whether Z. capensis has the ability to modify the proportion of nitrogenous waste in the excreta when protein intake and water intake varies. After 21 days of acclimation, plasma osmolality was not significantly affected by dietary treatment; however, excreta osmolality was higher in the high-protein group compared to the low-protein group. Nitrogenous wastes in Z. capensis are excreted mainly in the form of uric acid. The proportion of kidney devoted to medullary tissue was 40 % higher in dehydrated birds than in hydrated birds. Excreta osmolality was higher in dehydrated birds, and in... |
| Tipo: Journal article |
Palavras-chave: Granivory; Kidney; Nitrogenous waste; Osmoregulation; Passerines. |
| Ano: 2007 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2007000400006 |
| |
|
|
| HARTMAN BAKKEN,BRADLEY; SABAT,PABLO. |
| Nectar-feeding birds oscillate between avoiding overhydration when they are feeding and preventing dehydration during fasts. Here, we examined how resting rates of total evaporative water loss (TEWL) and metabolic water production (MWP) influence water balance in the green-backed firecrown (Sephanoides sephanoides), a Chilean hummingbird. We hypothesized that a circadian rhythm in TEWL would assuage the dehydration risk that hummingbirds face during the night. However, we did not find support for this idea. In resting hummingbirds, rates of TEWL during the day (54 ±6 µLh-1,n = 8) and night (65 ± 12 h-1, n = 5) were similar. Rates of MWP were also similar between the day (22 ±3 µL h-1, n = 8) and night (23 ± 2 µL h-1, n = 5). MWP rates were significantly... |
| Tipo: Journal article |
Palavras-chave: Circadian rhythm; Evaporative water loss; Hummingbird; Osmoregulation; Water balance. |
| Ano: 2007 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2007000300001 |
| |
|
|
| Tsuzuki,M.Y.; Ogawa,K.; Strüssmann,C.A.; Maita,M.; Takashima,F.; Melo,C.M.R.. |
| The role of cortisol on the osmoregulation of pejerrey Odontesthes bonariensis at different salinities was investigated in adult fish injected with 0.7mg hydrocortisone per 100g body weight of fish, and transferred to 0, 5 and 20ppt of NaCl. Blood cortisol was 566ng/ml at the beginning of the experiment (0h) but surged to 1250ng/ml within 3h in cortisol-injected fish. Cortisol levels were influenced not only by treatment but also by time, being higher at 3h compared to 24h. Salinity level, time of exposure and their interaction, but not cortisol treatment, significantly affected plasma osmolality and the concentration of ions Cl- and Na+. This study showed that exogenous cortisol does not seem to play a significant role on the regulation of plasma... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pejerrey; Odontesthes bonariensis; Cortisol; Osmoregulation; Salinity. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352007000500030 |
| |
|
|
| Prodocimo,Viviane; Souza,Carine F.; Pessini,Cristina; Fernandes,Luiz Claudio; Freire,Carolina A.. |
| The marine-estuarine species of pufferfishes Sphoeroides testudineus and S. greeleyi are very efficient osmoregulators. However, they differ with respect to their tolerance of salinity reduction. During low tide S. testudineus remains in diluted estuarine waters, whereas S. greeleyi returns to seawater (SW). The hypothesis tested here was that the short-term mobilization of metabolic substrates stored in their main osmoregulatory organs would correlate with this differential tolerance. Fishes exposed to 5 (for 6 h) were compared to those kept in 35. Branchial and renal contents of triglycerides, protein and glycogen were evaluated, and total ATPase activity accounted for the tissues' metabolism. Plasma osmolality, chloride and glucose, hematocrit, and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Fish gill; Fish kidney; Glycogen; Metabolism; Osmoregulation; Tetraodontidae. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252008000400009 |
| |
| Registros recuperados: 45 | |
|
|
|
