首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
We examined the ionoregulatory responses to temperature changes in two species of freshwater fish that differ in thermal preferences; the stenothermal, cold-water rainbow trout (Oncorhynchus mykiss) and the more eurythermal, warm-water common shiner (Notropis cornutus). We found that rainbow trout maintained constant plasma Na+ levels over the entire temperature regime (5–20 °C). Upon transfer from 15 °C (holding temperature) to 5 and 10 °C, rainbow trout experienced a significant drop in Na+ uptake (Jin Na), but after two weeks Jin Na had upregulated to warm temperature levels. Further, Na+ efflux (Jout Na) fell significantly at the colder temperatures. As a result, trout at the lowest temperatures were still in ion balance. When trout were exercised to exhaustion both O2 consumption (MO2) and Jout Na rose significantly at all temperatures, but while MO2 continued to be dependent upon temperature, Jout Na was high and constant. In contrast to the trout, common shiners experienced a 20% drop in plasma Na+ at 5 °C. Upon exposure to cold temperatures they experienced a reduced Jin Na, and showed no signs of acclimation during the subsequent two weeks. Likewise Jout Na was constant at all temperatures. These findings raise questions regarding the degree to which fish employ homeostatic mechanisms designed to defend a set- point (i.e., steady-state) osmolarity and ionic composition.  相似文献   

2.
With the aim of comparing the effects of oral T3 and NaCl administration on trout hypoosmoregulatory mechanisms, three groups of rainbow trout (Oncorhynchus mykiss Walbaum) held in freshwater (FW) were fed a basal diet (C), the same diet containing 8.83 ppm of 3,5,3-triiodo-L-thyronine (T3) (T) or 10% (w/w) NaCl (N) respectively for 30 d. They were then transferred to brackish water (BW) for 22 d and fed on diet C. Gill (Na++K+)-ATPase activity and its dependence on ATP, Na+ and pH, number of gill chloride cells (CC), serum T3 level as well as fish growth, condition factor (K) and mortality were evaluated. During the FW phase, as compared to C trout, T trout showed a two fold higher serum T3 level, had unchanged gill (Na++K+)-ATPase activity and increased CC number, whereas N trout showed higher gill (Na++K+)-ATPase activity and CC number. At the end of the experiment the enzyme activity was in the order T>N>C groups and all groups showed similar CC number. Both treatments changed the enzyme activation kinetics by ATP and Na+. A transient increase in K value occurred in N group during the period of salt administration. In BW, T and N groups had higher and lower survival than C group respectively. Other parameters were unaffected by the treatments. This trial suggests that T3 administration promotes the development of hypoosmoregulatory mechanisms of trout but it leaves the (Na++K+)-ATPase activity unaltered till the transfer to a hyperosmotic environment.  相似文献   

3.
The influence of cortisol on oxygen consumption and osmoregulatory variables was examined in coastal cutthroat trout (Oncorhynchus clarki clarki) parr kept in fresh water (FW) and transferred to seawater (SW). Intraperitoneal implants containing cortisol (50 g g–1) in vegetable oil resulted in elevated plasma cortisol titres similar to those observed in fish following a 24h SW exposure. Cortisol treatment significantly increased the oxygen consumption and plasma glucose levels of trout in FW, consistent with the glucocorticoid role of cortisol. Cortisol treatment did not cause any changes in plasma ion concentrations or gill Na+,K+-ATPase activity in FW after 10 days. Cortisol-implanted fish exposed to SW for 24h showed slightly improved ion regulatory ability compare to non-implanted controls. The results of this study suggest that during SW transfer in juvenile salmonids, increases in cortisol may act as both a mineralocorticoid and a glucocorticoid, depending on the developmental state of the fish (e.g., smolt versus parr). Furthermore, the relative energetic costs of osmoregulation and that of the stress associated SW transfer cannot be discerned using whole-animal oxygen consumption rates.  相似文献   

4.
Juvenile Atlantic salmon (Salmo salar), selected from the upper modal group, were first held for 122 days (from December to May) in freshwater, and then for 49 days in seawater (34% salinity). In freshwater, the fish were exposed to either standing water or water currents corresponding to a swimming speed of 1 Bl s–1. Natural light conditions prevailed throughout the whole experiment.In the freshwater phase, food intake, growth rate and condition factor of the fish increased with increasing daylength. Condition factors, however, decreased slightly during the last month of the freshwater period, suggesting that the fish underwent parr-smolt transformation. The growth rate and food intake of the fish subjected to standing water were approximately 15% lower than those of fish exposed to water currents.Transient suppression of appetite and growth, and an increase in plasma concentration of Cl–, were seen after exposure of the fish to seawater. Within 28 days, all these parameters had been restored to pre-transfer levels. Previous exercise did not appear to have influenced the hypoosmoregulatory capacity of the fish. Growth rate and food intake observed during the seawater phase were similar, irrespective of the treatment experienced by the fish during freshwater rearing.  相似文献   

5.
Proton pumps in the fish gill and kidney   总被引：2，自引：0，他引：2  
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   

6.
The involvement of the freshwater fish gill chloride cells (CCs) in trans-branchial calcium uptake (JinCa2+) was investigated. This was accomplished by assessing the interspecific relationships between the apical surface area of CCs exposed to the external environment and JinCa2+. Three species of freshwater teleosts, the rainbow trout (Oncorhynchus mykiss), the American eel (Anguilla rostrata) and the brown bullhead catfish (Ictalurus nebulosus), were used. Chronic (ten-day) treatment with cortisol in each species was used as a tool to evoke variations in both JinCa2+ and gill CC morphology in order to assess intraspecific relationships between CC surface area and JinCa2+. The results of quantitative morphometry, based on analysis of scanning electron micrographs, demonstrated that catfish possessed the lowest fractional area of exposed CC (CCFA) on the gill filament epithelium (12,744 ± 2248 m2/mm2) and was followed, in increasing order, by American eel (21,355 ± 981 m2/mm2) and rainbow trout (149,928 ± 26,545 m2/mm2). With the exception of catfish, chronic treatment with cortisol caused significant increases in CCFA owing to proliferation of CCs and/or enlargement of individual CCs (eel only). The rates of JinCa2+ closely reflected the CC fractional area in each species. The results of correlation analysis revealed significant correlations between CC fractional area and JinCa2+ in trout and eel. Owing to the absence of an effect of cortisol treatment, there was no significant correlation in catfish because of insufficient variation in CC fractional area in this species. CC fractional area was significantly correlated with JinCa2+ among the three species examined. These results suggest that CC is involved in calcium uptake in freshwater teleosts and that both intra- and interspecific differences in the rates of calcium uptake can be accounted for by variability in the surface area of exposed CCs on the gill epithelia.  相似文献   

7.
Whole animal transepithelial potentials (TEP) of yearling coho salmon (Oncorhynchus kisutch) in fresh water and after transfer to seawater were recorded throughout parr-smolt transformation (smoltification) from February to August 1984, along with plasma Na+ and Cl– concentrations and osmolality. Based on plasma ion regulation in seawater, the yearling coho in this study completed smoltification and attained sea-water adaptability in April. TEP in freshwater fish decreased (became inside-negative) after smoltification, and the TEP increased significantly (P < 0.01) after seawater transfer. When fish were transferred into seawater, thyroxine increased TEP of the transferred smolts by approximately 30% over the control level (P < 0.01) in April, but this did not occur when freshwater postsmolts were transferred in July and August. Hypophysectomy increased TEP (P < 0.01) in fresh water; it did not affect the TEP of the fish after seawater transfer. Ovine prolactin (3 g/g body weight) implanted into seawater-adapted fish caused a reduction in TEP (P < 0.01) when fish were exposed to fresh water. Whole-animal TEP appears to provide a valuable index of the completion of smoltification (April–May) and a useful tool for investigating the endocrine control of salmonid osmoregulation.  相似文献   

8.
Oxytetracycline (OTC), a broad-spectrum antibiotic, is used widely to treat bacterial diseases in farmed fish. In the present study, the time course of OTC concentrations in freshwater rainbow trout, Oncorhynchus mykiss (Walbaum), and seawater chinook salmon, Oncorhynchus tshawytscha (Walbaum), were compared, tissue by tissue, after receiving a bolus dose of the antibiotic (5 mg kg–1 or 50 mg kg–1) intra-arterially (i.a.). The OTC concentration–time profiles of rainbow trout tissues were found to be very similar to those of the corresponding tissues in chinook salmon. Therefore, neither water salinity nor fish species seemed to play an important role in the disposition and elimination of OTC in these salmonids. In a separate experiment, rainbow trout were implanted surgically with a urinary cannula and received a single dose of OTC (50 mg kg–1) i.a. Urine was collected from the cannula daily for 13 days. The amount of OTC excreted into the bile was found to be larger than that eliminated by the urine. These results show the similarity of OTC pharmacokinetics in freshwater rainbow trout and seawater chinook salmon and render support in using a single fish species to study the pharmacokinetics of a drug for other species in the same taxon.  相似文献   

9.
In salmonids, growth hormone (GH) effectively promotes adaptation of freshwater (FW) fish to seawater (SW), but it has been unclear whether GH has osmoregulatory actions apart from those consequent to an increase in body size. Our objectives were first, to examine the minimum time and dose required for GH to enhance SW adaptation; and second, to optimize the conditions for the acute GH response in developing a convenient GH bioassay based on its plasma ion lowering effect. Trout showed markedly improved SW survival when transferred from fresh water 6, 24, or 48h after a single chum salmon GH injection (0.25 μg/g). Preadapting trout to 1/3 SW enhanced the plasma ion lowering effect of ovine GH (oGH) injected 48h before transfer of the fish to 80% SW. Endogenous plasma GH levels were elevated in control trout switched from low salinities to 80% SW but were depressed in oGH-injected fish after transfer. Under optimal test conditions (1/3 SW preadaptation, 48h pre-transfer injection, and 100% SW final challenge), the reduction in plasma Na+, Ca++, and Mg++ levels of oGH-injected fish was dose-dependent. The oGH doses giving minimum and maximum responses were 50 and 200 ng/g, respectively. In short, GH exerts acute osmoregulatory actions that promote SW adaptation in the absence of changes in body size. Compared with growth GH bioassays, the osmoregulatory assay is superior in economy of time, animal costs, and hormone quantity required and potentially in specificity.  相似文献   

10.
The objective of this work was to determine whether highly unsaturated fatty acid (HUFA) synthesis and fatty-acid oxidation in Atlantic salmon (Salmo salar L.) intestine was under environmental and/or seasonal regulation. Triplicate groups of salmon were grown through a full two-year cycle on two diets containing either fish oil (FO) or a diet with 75% of the FO replaced by a vegetable oil (VO) blend containing rapeseed, palm, and linseed oils. At key points in the life cycle fatty acyl desaturation/elongation (HUFA synthesis) and oxidation activity were determined in enterocytes and hepatocytes using [1−14C]18:3n−3 as substrate. As observed previously, HUFA synthesis in hepatocytes reached a peak at seawater transfer and declined thereafter, with activity consistently greater in fish fed the VO diet. In fish fed FO, HUFA synthesis in enterocytes in the freshwater stage was at a level similar to that in hepatocytes. HUFA synthesis in enterocytes increased rapidly after seawater transfer, however, and remained high for some months after transfer before decreasing to levels that were again similar to those observed in hepatocytes. Enterocyte synthesis of HUFA was usually higher in fish fed the VO diet than in those fed the FO diet. Oxidation of [1−14C]18:3n−3 in hepatocytes from fish fed FO tended to decrease during the freshwater phase but then increased steeply, peaking just after transfer before decreasing during the remaining seawater phase. At the peak in oxidation activity around seawater transfer, activity was significantly lower in fish fed VO than in fish fed FO. In enterocytes, oxidation of [1−14C]18:3 in fish fed FO reached a peak in activity just before seawater transfer. In fish fed VO, except for high activity at nine months the pattern was similar to that obtained in enterocytes from fish fed FO, with high activity around seawater transfer and declining activity in seawater. In conclusion, fatty acid metabolism in intestinal cells seemed to be under dual nutritional and environmental or seasonal regulation. Temporal patterns of oxidation of fatty acids were usually similar in the two cell types, but HUFA synthesis in enterocytes peaked over the summer seawater phase rather than at transfer, as with hepatocytes, suggesting the possibility of different regulatory cues.  相似文献   

11.
王志远  李金库  李昀  王灵钰  齐鑫  李吉方  温海深 《水产学报》2023,47(8):089104-089104
为探究ncc、nkcc基因在花鲈渗透调节中发挥的作用,实验通过全基因组鉴定、多重序列比对、系统进化树构建以及蛋白结构预测对花鲈ncc进行了鉴定及序列分析,利用实时荧光定量PCR (qRT-PCR)检测ncc和nkcc在海水、淡水花鲈鳃组织中的表达水平,利用原位杂交技术确定ncc2和nkcc1a在海水及淡水花鲈鳃中的表达位置。结果显示,从花鲈中鉴定出2个ncc基因,即ncc1和ncc2,其编码序列(CDS)长度分别为2 691和3 120bp,编码896和1 039个氨基酸,在进化上具有保守性。ncc2在淡水花鲈鳃组织中的表达量显著高于海水,而nkcc1a在海水花鲈鳃组织中的表达量显著高于淡水,ncc1、nkcc1b、nkcc2在海淡水中的表达量则无显著差异。淡水适应过程中花鲈鳃组织中的ncc2的表达量逐渐上调,而nkcc1a的表达量逐渐下调;海水适应过程则呈现相反的表达趋势。此外,原位杂交结果显示,ncc2和nkcc1a基因分别位于淡水与海水中鳃组织的相邻鳃小片间的鳃丝上皮。以上结果表明,ncc2和nkcc1a基因分别编码淡水及海水花鲈鳃中重要的Na+及Cl  相似文献   

12.
The effect of cortisol on osmoregulatory parameters was studied in rainbow trout, (Salmo gairdneri), kept in freshwater (FW) and/or transferred to seawater (SW). Repeated injections of 20 μg cortisol/g fish stimulated gill and gut Na+/K+-ATPase activity and reduced plasma Na+ and Cl− levels after 2 weeks of treatment in FW-adapted fish. Cortisol doses of 0.05 and 1.0 μg/g were without effect. Repeated injections of 10 μg cortisol/g stimulated gill Na+/K+-ATPase activity and reduced plasma Na+ and Cl− levels in fish in FW, and significantly improved ion regulation after their transfer to 28SW. Higher doses of cortisol (10 and 20 μg/g) induced hyperglycemia, whereas low doses (0.05 and 1.0 μg/g were without effect or induced hypoglycemia. Plasma glucose levels decreased in cortisol-treated fish transferred to SW, whereas transient hyperglycemia was seen in the control fish.  相似文献   

13.
Do secondary sexual traits, such as large dorsal hump and hooked snout, decrease the swimming efficiency of male pink salmon during freshwater migration? This is the first study to address the effects of secondary sexual traits in pink salmon on oxygen uptake and swimming capacity. We conducted a laboratory experiment using a swimming respirometer and a field study using electromyogram (EMG) telemetry in the Shibetsu River, Hokkaido, Japan. We compared the relationship between MO2 (mg O2·kg?1·h?1) and swimming velocity U (m·s?1) in male and female fish, and also investigated the effects of morphological traits (secondary sexual characters) on the relationship between MO2 (mg O2·kg?1·h?1) and swimming velocity U (m·s?1). Additionally, we compared energy costs and swimming behaviour during upstream migration between male and female pink salmon. The laboratory experiment revealed that MO2 exponentially increased with increasing U; this increase was described by MO2 = 167.9e1.23U for males and 144.9e1.14U for females. Linear mixed models found that hump height and the upper jaw length in males significantly and positively affected the relationship between MO2 and U; no effect was found in females. The field study found that swimming velocity for both sexes estimated from EMG calibration was lower than optimal swimming velocity (Uopt) calculated from the laboratory experiment. We suggest that pink salmon in the Shibetsu River do not swim at the optimal swimming velocity because of the short migration distance involved (20 km).  相似文献   

14.
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   

15.
  相似文献   

16.
The effects of sub-lethal doses of dichlorvos and formalin, antimicrobial/parasitic agents used in aquaculture, on lipid composition and metabolism of rainbow trout skin cells in primary culture were investigated. [1-14C]Stearic (18:0), [1-14C]lin 18:2n-6) and [1-14C]linolenic (18:3n-3) acids were used as tracers to determine effects on fatty acid incorporation and metabolism. Formalin increased cell numbers and reduced the lipid content of the cells and the incorporation of radioactive fatty acids. The effects of dichlorvos were qualitatively similar but quantitatively less. Formalin induced relatively small but significant changes in lipid class composition including a decreased proportion of phosphatidycholine with increased proportions of sphatidylethanolamine and phosphatidylserine. Dichlorvos had no significant effect on lipid class compositions. The trout primary skin cells expressed substantial 9, 6 and 5 fatty acyl desaturase activities. Although, as expected, the cells were m active towards [1-14C]18:3n-3, the cells were unusually active towards [1-14C]18:2n-6. Both dichlorvos and, especially, formalin appeared to significantly inhibit 9 and 6 desaturation. Changes in the distribution of radioactivity between individual spholipid classes was also influenced by formalin and dichlorvos, and this may be related to changes in desaturase activity. This study has shown that topically active agents used in aquaculture, formalin and dichlorvos, had a range of effects on the rainbow trout skin cell cultures that may affect cell proliferation and lipid and fatty acid metabolism. Both agents significantly inhibited desaturation of fatty acids, particularly of 18:2n-6 to 20:4n-6 and, as 20:4n-6 is a major eicosanoid precursor ish and considering the importance of eicosanoids in the biochemistry of skin, it is suggested that these agents may have direct effects on fish skin that could have important consequences for fish health in general.  相似文献   

17.
The osmoregulatory ability of chum salmon (Oncorhynchus keta), reared in fresh water for a prolonged period, was examined by transferring them directly to seawater and then back to fresh water. When fry and juveniles weighing 0.3–125g, reared in fresh water for 1.5–13 months, were transferred directly to seawater, they adjusted their plasma Na+ concentration to the seawater-adapted level within 12–24h. When they were transferred back to fresh water after having been adapted to seawater for 2 weeks, the plasma Na+ level gradually decreased during the first 12–24h, and then increased to reattain the initial freshwater level after 5–7 days. No mortality was observed during the experiment except among the smallest fry weighing about 0.3g after transfer to seawater (2.1%). The maintenance of good osmoregulatory ability of the chum salmon for a prolonged period in fresh water seems to be unique among Pacific salmon, with the possible exception of the pink salmon.Changes in plasma levels of hormones during the transfer experiments were recorded in juveniles reared in fresh water for 13 months. Prolactin levels increased maximally 3 days after transfer from seawater to fresh water, as would be expected from its well-established role in freshwater adaptation in several euryhaline teleosts. In addition, an increase in plasma growth hormone was observed during the first 12h after seawater transfer, along with a tendency towards a decrease during freshwater transfer, suggesting an important role for this hormone in seawater adaptation. There were no consistent changes in plasma levels of thyroxine and cortisol during freshwater to seawater or seawater to freshwater transfer.  相似文献   

18.
An homologous radioimmunoassay for brown trout vitellogenin (VTG) was developed. Intact VTG, isolated from juvenile brown trout by selective precipitation and anion exchange chromatography was labelled with Na125I, with 1,3,4,6-tetrachloro-3,6-diphenylglycoluril (Iodogen) as the oxidizing agent. Incorporation of Na125I into VTG was higher than 75% and there was little degradation of the labelled protein. Labelled VTG eluted at the same position as unlabelled, purified brown trout VTG when analyzed by gel filtration on Sepharose 6B. Antisera with high titers, i.e. 1250 000, against brown trout VTG were raised in rabbits. The sensitivity of the assay was 5 ng VTG/ml and the standard curve was linear between 10 and 100 ng VTG/ml. Plasma from maturing female brown trout, as well as estradiol-treated and untreated juvenile brown trout diluted parallel to the standard curve, while plasma from maturing female rainbow trout and estradiol-treated arctic charr diluted non-parallel to the standard curve for brown trout VTG. Purified rainbow trout VTG and plasma from maturing female rainbow trout diluted parallel to each other, but with lower sensitivity than for brown trout VTG. Determinations of protein-bound phosphorus in the plasma of estradiol-treated juvenile brown trout correlated well with the RIA determinations of VTG. Repeated freezing and thawing of plasma samples yielded up to a hundred-fold increase in the apparent VTG level, while storage of a plasma sample for one year at –20°C did not affect the VTG level as measured by RIA.  相似文献   

19.
Fish growth hormones (GHs) play an important role in regulating growth, metabolism, reproduction, osmoregulation, and immunity and have thus garnered attention for their application in aquaculture. Zebrafish GH (zGH) cDNA or rainbow trout GH (rtGH) cDNA was cloned into the pMon3401 vector, expressed in MON105-competent Escherichia coli and purified to homogeneity. Their biological activity was evidenced by their ability to interact with ovine GH receptor extracellular domain and stimulate GH receptor-mediated proliferation in FDC-P1-3B9 cells stably transfected with rabbit GH receptor. The relative affinity of zGH and rtGH, estimated by IC50, was about 38-fold and 512-fold lower, respectively, than ovine GH. This is likely the reason for the low biological activity in cells with rabbit GH receptor, ~?36-fold lower for zGH and ~?107-fold lower for rtGH than for human GH. This was not due to improper refolding, as evidenced by circular dichroism analysis. Predicting the activity of fish GHs is problematic as there is no one single optimal in vitro bioassay; heterologous assays may be ambiguous, and only homologous assays are suitable for measuring activity.  相似文献   

20.
We have isolated a cDNA encoding the taurine transporter from a tilapia (Oreochromis mossambicus) gill cDNA library. Transient expression of the cDNA in COS-7 cell indicates that the clone encodes a Na+- and Cl–-dependent and -amino acid-specific taurine transporter. By the transfer of tilapia cultured in freshwater to 70% artificial seawater, plasma osmolality increased by up to 100–135 mOsm/kgH2O along with the marked increase in the taurine transporter mRNA level in all the tissues examined i.e., kidney, stomach, intestine, gill, eye, liver, fin, muscle and brain. In most tissues, time-dependent change in the taurine transporter mRNA level corresponds to that in plasma osmolality. However, fin showed an acute and muscle showed a delayed increase in taurine transporter mRNA compared to changes in plasma osmolality. The taurine transporter mRNA level in tilapia embryos also increased after transfer from freshwater to 100% artificial seawater. Increase in taurine transporter expression leads to the activation of cellular uptake of taurine from plasma and the accumulation of taurine in the cell. Thus the results in the present study suggest that taurine plays an important role as an osmolyte in the ubiquitous tissues of tilapia during high-salinity adaptation.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号