Interaction of salinity (NaCl) and cadmium (Cd) on growth, mineral nutrients, Na and Cd accumulation in four barley genotypes differing in salt tolerance was studied in a hydroponic experiment. Cd, NaCl and their combined stresses reduced Ca and Mg concentrations in roots and shoots, K concentration in shoots, increased K and Cu concentrations in roots relative to control, but had non-significant effect on micronutrients Cu, Fe and Mn concentrations in shoot. The three stresses reduced accumulation of most tested nutrients in both roots and shoots, except NaCl and NaCl+Cd stresses for root K and shoot Cu accumulation in salt tolerant genotypes. The salt tolerant genotypes did not have higher nutrient concentration and accumulation than the sensitive ones when exposed to Cd and NaCl stresses. In conclusion, the affecting mechanism of Cd stress on nutrients was to some extent different from salinity stress, and the NaCl+Cd stress was not equal to additional Cd and NaCl stresses, probably due to the different valence and competitive site of Na(+) and Cd(2+). NaCl addition in the Cd-containing medium caused remarkable reductions in both Cd concentration and accumulation, with the extent of reduction being also dependent on genotypes. The salt-tolerant genotypes had lower Na concentration than sensitive ones.
Cadmium ; metabolism ; toxicity ; Chlorophyll ; metabolism ; Genotype ; Hordeum ; drug effects ; genetics ; metabolism ; Minerals ; metabolism ; Sodium ; metabolism ; Sodium Chloride

Atropa belladonna seedlings were used as experimental materials and cultivated by soil culture method. Different concentrations(0,0.05,0.1,0.2,0.5 mmol·L~(-1))of NO donor sodium nitroprusside(SNP) were sprayed on the leaves. The effects of different concentrations of SNP and different treatment time(4,8,12,16 d) on nitrogen metabolism, secondary metabolite content, precursor content of tropane alkaloid synthesis pathway and expression of key enzyme genes under 100 mmol·L~(-1) NaCl stress were studied. The results showed that with the prolongation of salt stress, the nitrogen metabolism and the accumulation of secondary metabolites of A. belladonna were inhibited to some extent. After treatment with different concentrations of exogenous SNP, the ammonium nitrogen content decreased dramatically, and the contents of nitrate nitrogen, free amino acid, soluble protein and the activities of key enzymes of nitrogen metabolism(NR, GS, GDH) were all greatly improved; the contents of precursor amino acids(ornithine, arginine) and polyamines(Put, Spd, Spm) in the secondary metabolic pathway have increased to varying degrees. The qRT-PCR analysis showed that exogenous SNP treatment can effectively promote the high expression of key enzyme genes PMT, TRⅠ and H6H in the secondary metabolic pathway of A. belladonna, and the production of hyoscyamine and scopolamine were increased notably. In summary, the application of appropriate concentration of SNP can effectively alleviate the inhibition of salt stress on the nitrogen metabolism and secondary metabolism of Atropa belladonna, and enhance its salt tolerance. Overall, 0.1 mmol·L~(-1) and 0.2 mmol·L~(-1) SNP treatment achieved the most remarkable effect.
Atropa belladonna/metabolism* ; Hyoscyamine/analysis* ; Nitrogen/metabolism* ; Nitroprusside ; Scopolamine/analysis* ; Secondary Metabolism ; Sodium Chloride ; Stress, Physiological

OBJECTIVETo determine whether the GABA-containing neurons in rat central nucleus of amygdala (CeA) can be activated by acute sodium deprivation.

METHODSAcute sodium depletion was induced by subcutaneous injection of furosemide in rats followed by 24 h of dietary sodium deprivation. The rats underwent 0.3 mol/L NaCl/distilled water two bottle choice test, and the activated neurons were labeled and identified with GABA/Fos-double labeling immunohistochemistry.

RESULTSThe rats with acute sodium depletion exhibited significantly more numerous c-fos-positive neurons and GABA/Fos double-labeled neurons in the CeA than the control group (P<0.01, P<0.05). Consumption of 0.3 mol/L NaCl significantly increased the number of c-fos and GABA/Fos double labeled neurons compared to the distilled water group (P<0.001, P<0.01).

CONCLUSIONGABAergic neurons in the CeA may play an inhibitory role in the regulation of sodium intake in rats with acute sodium depletion.

Amygdala ; cytology ; metabolism ; Animals ; GABAergic Neurons ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley ; Sodium Chloride, Dietary ; metabolism ; Sodium, Dietary

To study the roles of glucosylglycerol phosphate synthase (Ggps) in glucosylglycerol (GG) and glycerol biosynthesis, we over-expressed Ggps from either Synechocystis sp. PCC 6803 or Synechococcus sp. PCC 7002 in a Synechocystis strain with a high GG titer, and determined the GG and glycerol accumulation in the resultant mutants grown under different NaCl-stress conditions. Ion chromatography results revealed that GG yield was not improved, but glycerol production was significantly enhanced by over-expression of Ggps from Synechocystis sp. PCC 6803 (6803ggpS). In addition, increasing the NaCl concentration of medium from 600 to 900 mmol/L led to a further 75% increase of glycerol accumulation in the mutant strain with 6803ggpS over-expression. These findings show the role of ggpS in driving the carbon flux to the glycerol biosynthesis pathway, and will be helpful for further improvement of GG and glycerol production in Synechocystis.
Bacterial Proteins ; metabolism ; Culture Media ; Glucosides ; biosynthesis ; Glucosyltransferases ; metabolism ; Glycerol ; metabolism ; Industrial Microbiology ; Sodium Chloride ; Synechococcus ; enzymology ; Synechocystis ; enzymology ; metabolism

OBJECTIVETo investigate the influence of salinity variations on the performance of activated sludge systems, treating domestic wastewater.

METHODSThe completely mixed reactor was used and operated in a batch-wise mode. The activated sludge taken from the Gaobeidian Wastewater Treatment Plant was used as a seeding sludge. Total organic carbon (TOC), oxygen uptake rate (OUR) and suspended solids (SS) were used as parameters to characterize the performance of the treatment systems. TOC was measured using a TOC-analyzer (TOC-5000, Japan). The OUR value was measured with a dissolved oxygen meter (YSI model-58). SS was measured gravimetrically.

RESULTSThe TOC removal efficiency and the OUR value of activated sludge were not deteriorated when the NaCl shock concentration was less than 0.5 g/L. However, when the NaCl shock concentrations were up to 10g/L and 20 g/L, the OUR of activated sludge was reduced by 35% and TOC removal efficiency was dropped by 30%, compared with the control experiment without NaCl shock loading.

CONCLUSIONThe effect of NaCl shock loading on the activated sludge wastewater treatment system is dependant upon the NaCl concentrations and the degree of influence can be inferred through the change of substrate utilization rate at different shock NaCl loadings.

Bioreactors ; Carbon ; analysis ; Oxygen ; metabolism ; Sewage ; chemistry ; Sodium Chloride ; Waste Disposal, Fluid

The kidney is one of the main target organs involved in hypertension, and it regulates water and salt metabolism, blood volume and vascular resistance. High salt intake induces salt and water retention, persistent endothelial dysfunction and elevation of blood pressure in salt sensitive individuals. Dahl salt sensitive (Dahl-SS) rats, as a classic animal model for salt sensitive hypertension, have many similar stably inherited physiological characteristics to human with salt sensitive hypertension, such as salt sensitivity, hyperlipidemia, insulin resistance, renal failure, increased urinary protein secretion and low plasma renin activity. Based on renal physiology and biochemistry researches and multi-omics analyses in Dahl-SS rats, this review will summarize the relationship between salt sensitive hypertension and renal redox, NO, amino acids, glucose and lipid metabolism.
Animals ; Blood Pressure ; Hypertension ; Kidney/metabolism* ; Rats ; Rats, Inbred Dahl ; Sodium Chloride, Dietary

The effects of salinity (50 mmol/L NaCl) and Cd (1 micromol/L CdCl(2)) as sole and combined on growth and photosynthetic parameters were studied using two soybean genotypes, Huachun 18 and NGB. The concentrations of Cd(2+), Zn(2+), Ca(2+), Mg(2+), K(+) and Na(+) were also determined in seeds and pods. Huachun 18 suffered a more serious decrease than NGB in net photosynthetic rate (P(n)) in the treatments of salinity stress alone and combined stress (NaCl+Cd), showing that it is relatively sensitive to salinity. The decrease in P(n) caused by salt stress in Huachun 18 was mainly due to the reduced total chlorophyll content and photosynthetic efficiency (the ratio of variable fluorescence to maximal fluorescence, F(v)/F(m)), whereas the decease in NGB was mainly related to reduced stomatal conductance (G(s)). The combined stress of both Na and Cd did not induce further decrease in photosynthesis and fluorescence in the two genotypes relative to salt or Cd stress alone. Greater change in the pod concentrations of Zn(2+), Ca(2+), Mg(2+), K(+) and Na(+) was detected under salt stress for Huachun 18 than for NGB. The results suggested that the interactive effect of NaCl-Cd on growth and nutrient uptake differs between the two soybean genotypes.
Cadmium Chloride ; administration & dosage ; metabolism ; Osmotic Pressure ; Photosynthesis ; drug effects ; Sodium Chloride ; administration & dosage ; metabolism ; Soil ; analysis ; Soybeans ; drug effects ; growth & development ; metabolism

Hemodynamic factors play an important role in the development and/or progression of diabetic nephropathy. We hypothesized that renal sodium transporter dysregulation might contribute to the hemodynamic alterations in diabetic nephropathy. Otsuka Long Evans Tokushima Fatty (OLETF) rats were used as an animal model for type 2 diabetes. Long Evans Tokushima (LETO) rats were used as controls. Renal sodium transporter regulation was investigated by semiquantitative immunoblotting and immunohistochemistry of the kidneys of 40-week-old animals. The mean serum glucose level in OLETF rats was increased to 235+/-25 mg/dL at 25 weeks, and the hyperglycemia continued up to the end of 40 weeks. Urine protein/ creatinine ratios were 10 times higher in OLETF rats than in LETO rats. At 40th week, the abundance of the epithelial sodium channel (ENaC) beta-subunit was increased in OLETF rats, but the abundance of the ENaC gamma-subunit was decreased. No significant differences were observed in the ENaC alpha-subunit or other major sodium transporters. Immunohistochemistry for the ENaC beta-subunit showed increased immunoreactivity in OLETF rats, whereas the ENaC gamma-subunit showed reduced immunoreactivity in these rats. In OLETF rats, ENaC beta-subunit upregulation and ENaC gamma-subunit downregulation after the development of diabetic nephropathy may reflect an abnormal sodium balance.
Animals ; Blood Glucose/analysis ; Diabetes Mellitus, Type 2/*metabolism ; *Disease Models, Animal ; Epithelial Sodium Channel/*analysis ; Hypertension/complications ; Immunoblotting ; Immunohistochemistry ; Kidney/*metabolism ; Male ; Rats ; Sodium/*metabolism ; Sodium-Hydrogen Antiporter/genetics ; Sodium-Potassium-Chloride Symporters/genetics

Licorice seedlings were taken as experimental materials, an experiment was conducted to study the effects of exogenous sucrose on growth and active ingredient content of licorice seedlings under NaCl stress conditions. The results of this study showed that under salt stress conditions, after adding a certain concentration of exogenous sucrose, the licorice seedlings day of relative growth rate was increasing, and this stress can be a significant weakening effect, indicating that exogenous sucrose salt stress-relieving effect. The total flavonoids and phenylalanine ammonia lyase (PAL) activity were significantly increased, the exogenous sucrose can mitigated the seedling roots under salt stress, the licorice flavonoid content in the enhanced growth was largely due to the activity of PAL an increased, when the concentration of exogenous sucrose wae 10 mmol x L(-1), PAL activity reaching a maximum, when the concentration of exogenous sucrose was 15 mmol x L(-1), PAL activity turned into a downward trend, the results indicating that this mitigation has concentration effect. After applying different concentrations of exogenous sugar, the contents of liquiritin changes with the change of flavonoids content was similar. After applying different concentrations of exogenous sucrose, the content of licorice acid under salt stress was higher than the levels were not reached during salt stress, the impact of exogenous sucrose concentration gradient of licorice acid accumulation was not obvious.
Drugs, Chinese Herbal ; analysis ; metabolism ; Glycyrrhiza ; chemistry ; growth & development ; metabolism ; Plant Roots ; chemistry ; growth & development ; metabolism ; Seedlings ; chemistry ; growth & development ; metabolism ; Sodium Chloride ; metabolism ; Sucrose ; metabolism

OBJECTIVEIn order to get the method for improving the salt resistance of Hedysarum polybotrys seeds and seedlings under different salt-alkaline stress, the seed germination and physiological characteristics of H. polybotrys seedlings were studied.

METHODSeveral physiological indexes of H. polybotrys seeds under different salt-alkaline stress, such as the germination vigor, germination rate, relative germination rate, relative salt damage rate were measured. And others indexes of the seedlings like chlorophyll contents, soluble protein contents, the permeability of plasmalemma, the activities of POD and SOD were also measured.

RESULTDifferent salt-alkaline stress decreased the germination rate, vigor of germinate, germination index, while relative salt damage rate increased. With the increased salt-alkaline concentration, the adverse effects became more obvious. The strength of the salts: Na2CO3 > Na2SO4 > NaCl. With the increase of the salt-alkaline concentration, the chlorophyll contents and the soluble protein contents decreased, but the permeability of plasmalemma increased. The change trend of SOD and POD activity was similar, it is increased firstly, and then decreased as the stress intensity extended, the most significant increase of Na2SO4 and Na2CO3 in the concentration of salt-alkaline was 25 mmol x L(-1), but NaCl was 50 mmol x L(-1).

CONCLUSIONThe seeds and seedlings inhibition of the salts was Na2CO3 > Na2SO4 > NaCl.

Alkalies ; metabolism ; Fabaceae ; growth & development ; metabolism ; physiology ; Seedlings ; growth & development ; metabolism ; physiology ; Seeds ; growth & development ; metabolism ; physiology ; Sodium Chloride ; metabolism ; Stress, Physiological