SEARCH · Search PubMed

Results for “salinity tolerance”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17Linked to original sources

PubMed1990

Osmoregulation of the salt-tolerant yeast Debaryomyces hansenii grown in a chemostat at different salinities.

The intracellular solute composition of the salt-tolerant yeast Debaryomyces hansenii was studied in glucose-limited chemostat cultures at different concentrations of NaCl (4 mM, 0.68 M, and 1.35 M). A strong positive correlation between the total intracellular polyol concentration (glycerol and arabinitol) and medium salinity was demonstrated. The intracellular polyol concentration was sufficient to balance about 75% of the osmotic pressure of the medium in cultures with 0.68 and 1.35 M NaCl. The intracellular concentration of K+ and Na+, which at low external salinity gave a considerable contribution to the intracellular water potential, was only slightly enhanced with raised medium salinity. However, the ratio of intracellular K+ to Na+ decreased; but this decrease was less drastic in the cells than in the surrounding medium, i.e., the cells were able to select for K+ in favor of Na+. The turgor pressure, which was estimated on the basis of intracellular solute concentrations, was 2,200 kPa in cultures with 4 mM NaCl and decreased when the external salinity was raised, resulting in a value of about 500 kPa in cultures with 1.35 M NaCl. The maintenance of a positive turgor pressure at high salinity was mainly due to an increased production and accumulation of glycerol.

Glucose↗

PubMed2006

Response to selection and evolvability of invasive populations.

While natural selection might in some cases facilitate invasions into novel habitats, few direct measurements of selection response exist for invasive populations. This study examined selection response to changes in salinity using the copepod Eurytemora affinis. This copepod has invaded fresh water from saline habitats multiple times independently throughout the Northern Hemisphere. Selection response to a constant intermediate salinity (5 PSU) was measured in the laboratory for saline source and freshwater invading populations from the St. Lawrence drainage (North America). These populations were reared under three conditions: (1) native salinities (0 or 15 PSU) for at least two generations, (2) 5 PSU for two generations, and (3) 5 PSU for six generations. Full-sib clutches taken from populations reared under these three conditions were split across four salinities (0, 5, 15, and 25 PSU) to determine reaction norms for survival and development time. Contrasts in survival and development time across the three rearing conditions were treated as the selection response. Selection at 5 PSU resulted in a significant decline in freshwater (0 PSU) tolerance for both the saline and freshwater populations. Yet, evolutionary differences in freshwater tolerance persisted between the saline and freshwater populations. The saline and freshwater populations converged in their high-salinity (25 PSU) tolerance, with an increase in the freshwater population and decline in the saline population. Development time did not shift greatly in response to selection at 5 PSU. For all three rearing conditions, the freshwater population exhibited retarded larval development and accelerated juvenile development relative to the saline population. Results from this study indicate that both the saline and freshwater populations exhibit significant responses to selection for a fitness-related trait critical for invasions into a novel habitat.

Animals↗

PubMed1994

Differential regulation of the behavioral effects of chlordiazepoxide.

Chronic administration of the benzodiazepine (BZ) receptor agonist chlordiazepoxide (CDP) produced tolerance to its motor-impairing effects but little or no tolerance to its hypothermic effects or to its amnesic effects in the radial arm maze. Male Sprague-Dawley rats were pretreated for 14 days with CDP (25 mg/kg, b.i.d., IP) or saline, and chronic treatment was maintained throughout the experiments. Tolerance was evaluated by constructing dose-response curves to CDP following chronic administration of either CDP or saline. Tolerance developed to only certain behavioral effects of CDP. Tolerance developed to the motor-impairing effects of CDP as assessed in three different procedures: rotarod, spontaneous locomotor activity, and acquisition of the step-through inhibitory avoidance response. In contrast, tolerance did not develop to the hypothermic effects of CDP. Tolerance to the amnesic effects of CDP was contingent upon the behavioral procedure. For example, tolerance developed to reductions of retention latency in the step-through inhibitory avoidance response, but not to impairment of the acquisition of radial arm maze performance. These results are consistent with the effects of chronic BZ administration in humans and demonstrate a parallel regulation of drug effects, potentially mediated by regional differences in BZ receptor subtype regulation or composition.

Amnesia↗

PubMed1995

Selenium assimilation and differential response to elevated sulfate and chloride salt concentrations in two saltgrass ecotypes.

A comparative study of selenium (Se) assimilation under the influence of sulfate and chloride salt salinity was conducted on two saltgrass ecotypes. The inland saltgrass grows successfully on the soil contaminated with elevated Se concentrations at Kesterson, Merced County, California. The coastal saltgrass colonizes a tidal salt marsh in Bodega Bay on the coast of California. The saltgrass samples were grown in sand culture and irrigated with quarter concentration of modified Hoagland solution supplemented with different concentrations of Se with or without sulfate or chloride salt. The Bodega Bay plants exhibited greater tolerance to both the sulfate and chloride salinity than the Kesterson plants. The plants of both ecotypes accumulated about 90% of their total tissue Se in the nonprotein fraction. When sulfate was present in the irrigation solution, the Kesterson plants assimilated significantly less Se in its protein and nonprotein fractions than in the Bodega Bay plants. Under Se treatment, chlorosis symptoms were found on the leaves of the Bodega Bay plants, but not on the leaves of the Kesterson plants. The above results demonstrate that the two saltgrasses are distinct ecotypes in respect to their salinity tolerance and the ability of mitigation of selenium assimilation in the presence of sulfate.

California↗

PubMed1998

In Vitro Propagation of Salt-Tolerant Wild Rice Relative, Porteresia coarctata Tateoka.

Micropropagation of Porteresia coarctata Tateoka, a wild relative of rice with useful genetic traits of salinity and submergence tolerance, was achieved through nodal segment culture. Woody Plant (WP) medium supplemented with benzyladenine (5.5 µm) and kinetin (2.3 µm) gave the greatest response to initiation and multiplication. The multiplication rate of 11 shoots/explant with an average shoot length of 3.5 cm was observed after 8 weeks of culture period. The rooting response was observed simultaneously in the multiplication media, but subsequent establishment was poor. When the in vitro raised shoots were transferred to optimal 1/2 WP and 1/2 MS media with 10.7 µm alpha-naphthaleneacetic acid, the rooting response was enhanced. Such rooted plants were hardened successfully under field conditions. Key Words. Conservation-Mangrove associates-Micropropagation-Nodal explants-Porteresia coarctata-Salt tolerance

Journal Article↗

PubMed2026

Identification and analysis of HD-ZIP transcription factors that regulate salt gland development and salt tolerance in Limonium bicolor.

Soil salinity severely constrains agricultural production. Elucidating the salt-tolerance mechanisms of halophytes can provide innovative approaches for improving the salt tolerance of crop plants. In this study, we performed genome-wide identification and analysis of 36 LbHDZ genes encoding homeodomain-leucine zipper (HD-ZIP) transcription factors in Limonium bicolor, a typical recretohalophyte that excretes excess salt ions through specialized salt glands. Expression profiling across different stages of salt gland development, as well as in various tissues under salt stress, indicated that multiple LbHDZ genes are involved in regulating salt gland development and salt tolerance. Among these genes, LbHDZ14 (a member of the HD-ZIP II subfamily) exhibited sustained high expression during the critical period of salt gland formation, while its transcript levels were significantly downregulated in leaves and roots under salt stress. Subsequent experiments demonstrated that LbHDZ14 is localized in the nucleus and negatively regulates salt gland density and salt tolerance by directly binding to the promoter of LbGDSL, a positive regulator of salt gland development. In conclusion, this study reveals the expression patterns of LbHDZ genes in L. bicolor, characterizes the functional mechanism of LbHDZ14, further elucidates the regulatory network underlying salt gland development, and provides candidate genes for enhancing crop salt tolerance.

Plumbaginaceae↗

PubMed1979

Effects of the synthetic enkephalin analogue FK 33-824 on pain threshold and pain tolerance in man.

Natural enkephalins exert weak and transitory analgesic effects. The synthetic enkephalin, FK 33-824 (FK), is less susceptible to metabolic breakdown and produces long-lasting analgesia in animals. The present studies examined the effects of FK on threshold and tolerance of electrically evoked pain in man under double blind conditions. 1.0 mg FK given intramuscularly (saline control) increased tolerance significantly without affecting the pain threshold, but also produced vasodilatation and feelings of oppression and heaviness (study I). In study II, where 50 mg betazole was employed as "placebo" because of its vasodilatatory effects, 1.0 mg FK increased pain tolerance significantly more than 0.25 mg FK while the threshold remained unchanged. Self-ratings of activation and well-being decreased; those of oppression increased, as did reaction time, equally after 0.25 and 1.0 mg FK but were not altered by betazole. In conclusion, 1.0 mg FK i.m. increases tolerance but not perception of pain, thus mimicking the analgesic effects of morphine.

Adult↗

PubMed2000

Opioid tolerance induced by metamizol (dipyrone) microinjections into the periaqueductal grey of rats.

Non-opioid analgesics have been shown to elicit antinociception by an action upon central nervous system structures, in addition to their well known action upon peripheral tissues. Microinjection of metamizol (dipyrone), a widely used nonopioid analgesic, into the periaqueductal grey matter (PAG) of rats activates pain-modulating systems in the nucleus raphe magnus and inhibits spinal nociceptive neurons and the tail-flick reflex. Since these effects involve an activation of endogenous opioidergic systems, the possibility that metamizol induces opioid tolerance was investigated. Microinjection of metamizol into the ventrolateral PAG in awake rats induced antinociception, as demonstrated in the heat-elicited tail flick and hot plate tests. When microinjected into the ventrolateral PAG twice daily for 2 days, metamizol induced tolerance, i.e. a progressive loss of its antinociceptive effect. In contrast to rats repeatedly microinjected with saline, metamizol-tolerant rats were also tolerant to morphine microinjection into the same PAG site, and displayed signs of opioid withdrawal upon systemic administration of naloxone. These and other results suggest that metamizol activates endogenous opioid systems and that nonopioid analgesics may, by an action upon the central nervous system, lead to opioid tolerance and the risk of opioid withdrawal.

Animals↗

PubMed2001

Tolerance of Bradyrhizobium sp. (Lupini) strains to salinity, pH, CaCO3 and antibiotics.

AIMS: Ten rhizobial isolates obtained from different locations in Egypt were examined for their ability to survive under stress conditions and their growth response to increasing levels of NaCl (1-8% w/v), pH (4-10), CaCO3 (1-10% w/v) and 12 antibiotics. METHODS AND RESULTS: All the rhizobial isolates tolerated a NaCl concentration up to 5% and were divided into two groups with respect to NaCl tolerance. The rhizobial isolates from group two showed significantly (P < 0.05) better survival under high NaCl concentration. All the tested isolates survived acidic (pH 4-5) and alkaline conditions (pH 9-10) and CaCO3 (up to 10% w/v) in liqued YEM medium. CONCLUSION: Antibiotic resistance patterns did not correlate to NaCl, pH or CaCO3 tolerance. Variations among different strains showed that there is potential to improve strain performance under stress conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: The results suggest that selection of adapted strains under stress conditions is possible and can be used as inoculants for successful lupin growth.

Anti-Bacterial Agents↗

PubMed1990

[Preparation for colonoscopy using Golytely--a sure method? Comparative histological and clinical study between lavage and saline laxatives].

UNLABELLED: Looking at clinical side-effects, effectiveness and tolerability, we compared the salinic solution "Golytely" vs. a conventional preparatory procedure (Cascara-Salax) in a prospective study including 28 patients with macroscopic normal mucosa. Mucosal changes in colonic step biopsies were investigated according to prefixed criteria. RESULTS: There was no significant difference concerning weight, blood pressure, pulse rate, body temperature or essential laboratory findings. Whereas preparation using Cascara-Salax was less molesting stated by the patients, there was no difference in the way colonoscopy itself was tolerated in both groups. The performing doctor's evaluation of the colonic cleaning effect and examination conditions showed "Golytely" significantly ahead of Cascara-Salax. Histologically, colonic mucous layers depicted changes in the control groups in 63% vs. 40% in the "Golytely" group. "Golytely" seems to provide a safe and effective method of preparation for colonoscopy.

Colon↗

PubMed2001

A catalytic subunit of the sugar beet protein kinase CK2 is induced by salt stress and increases NaCl tolerance in Saccharomyces cerevisiae.

Salinity is an important limiting factor in plant growth and development. We have cloned a catalytic subunit of the sugar beet protein kinase CK2 (BvCKA2) by functional expression in yeast of a NaCl-induced cDNA library. BvCKA2 was able to increase the yeast tolerance to NaCl and to functionally complement the cka1 cka2 yeast double mutant upon over-expression. Southern blot analysis indicated that, in sugar beet, the BCKA2 gene is a member of a multigene family. The mRNA levels of BvCKA2 were up-regulated in response to NaCl stress which suggests that protein kinase CK2 may be involved in the plant response to salt stress.

Adaptation, Physiological↗

PubMed2006

Gain- and loss-of-function mutations in Zat10 enhance the tolerance of plants to abiotic stress.

C(2)H(2)-zinc finger proteins that contain the EAR repressor domain are thought to play a key role in modulating the defense response of plants to abiotic stress. Constitutive expression of the C(2)H(2)-EAR zinc finger protein Zat10 in Arabidopsis was found to elevate the expression of reactive oxygen-defense transcripts and to enhance the tolerance of plants to salinity, heat and osmotic stress. Surprisingly, knockout and RNAi mutants of Zat10 were also more tolerant to osmotic and salinity stress. Our results suggest that Zat10 plays a key role as both a positive and a negative regulator of plant defenses.

Abscisic Acid↗

PubMed2000

Container-grown tree seedling responses to sodium chloride applications in different substrates.

Seedlings of Norway maple (Acer platanoides), silver birch (Betula pendula), Norway spruce (Picea abies) and Scots pine (Pinus sylvestris) were grown in selected sodium chloride (NaCl) concentrations, soil types and under different watering regimes. Plants were raised from seeds, except for Scots pine plants which were obtained from a commercial source. Among the plant species tested, Scots pine was the most tolerant to soil salinity, while Norway spruce was the most susceptible. For both Norway maple and Norway spruce some half-sib families were more tolerant than others. No significant correlation was found between the tolerance of different half-sib families and the tolerance of mother trees observed in the field. The extent of leaf necrosis correlated significantly with the leaf concentrations of sodium (Na) and chloride (Cl). Among half-sib families within the species no such correlation was found. On the other hand, the least injured progeny of Norway maples had the highest concentrations of NaCl. The extent of salt-induced leaf necrosis varied with soil type, and a significant interaction between species and soil type was observed. Seedlings of Norway spruce grown in sand showed more severe necrosis and significantly higher concentrations of Na and Cl than seedlings grown in loam, silt loam, and peat. The severity of salt-induced leaf injury varied with the watering regime. Silver birch was the most affected species by drought and autumn watering treatments. Plants of silver birch subjected to drought showed increased leaf necrosis compared to the non-treated plants, and autumn watering treatment reduced the severity of leaf necrosis.

Journal Article↗

PubMed2005

Salinity stress adaptation competence in the extremophile Thellungiella halophila in comparison with its relative Arabidopsis thaliana.

In stark contrast to Arabidopsis, a related species, Thellungiella halophila (Thellungiella salsuginea; salt cress), displays extreme tolerance to high salinity, low humidity and freezing. High nucleotide sequence identity permits the use of tools developed for Arabidopsis for Thellungiella transcript profiling, for which a microarray platform with >25,000 DNA elements (70-mer oligonucleotides) was used. Microarray transcript profiling and intensity analysis, quantitative RT-PCR, and metabolite profiles define genes and pathways that showed shared and divergent responses to salinity stress in the two species. Shared responses are exemplified by 40% of the regulated genes functioning in confining ribosomal functions, photosynthesis and cell growth, as well as activating osmolyte production, transport activities and abscisic acid-dependent pathways. An additional 60% of regulated genes distinguished Thellungiella from Arabidopsis. Analysis of the differences showed that Arabidopsis exhibited a global defense strategy that required bulk protein synthesis, while Thellungiella induced genes functioning in protein folding, post-translational modification and protein redistribution. At 150 mm NaCl, Thellungiella maintained unimpeded growth. Transcript intensity analyses and metabolite profiles supported the microarray results, pointing towards a stress-anticipatory preparedness in Thellungiella.

Adaptation, Physiological↗

PubMed1994

Modulation of morphine tolerance by the competitive N-methyl-D-aspartate receptor antagonist LY274614: assessment of opioid receptor changes.

Recent reports have demonstrated that the coadministration of morphine with an N-methyl-D-aspartate (NMDA) receptor antagonist can attenuate and/or reverse the development of morphine tolerance. In the present study we used an experimental tolerance paradigm using morphine pellets (75 mg) to produce an 1-fold shift in the morphine dose-response curve in rats. Coadministration of the competitive NMDA receptor antagonist LY274614 [(+-)-6-phosphonomethyl-decahydroisoquinolin-3-carboxylic acid] via continuous s.c. infusion (24 mg/kg/24 hr) significantly attenuated the development of morphine tolerance. In addition, animals made tolerant to morphine and then infused with LY274614 (24 mg/kg/24 hr) regained their analgesic sensitivity to morphine more rapidly than morphine-tolerant animals given a saline infusion. To determine whether LY274614 treatment modifies the subsequent development of tolerance, LY274614 was administered to nontolerant animals for 1 week. One week after LY274614 treatment was discontinued the animals were challenged with morphine and then implanted with morphine pellets. Neither the expression of morphine analgesia nor the development of morphine tolerance differed when LY274614- and saline-treated animals were compared. The infusion of LY274614 for 7 days did not increase the affinity or density of mu, delta, kappa-1 or kappa-3 opioid receptors in rat brain homogenates as measured by ligand binding assays. Additionally, the IC50 values for LY274614 in mu-1, mu-2, delta, kappa-1 or kappa-3 ligand binding assays were greater than 10 microM. Taken together these results demonstrate that the competitive NMDA receptor antagonist LY274614 can both attenuate and reverse the development of morphine tolerance.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

PubMed2026

Transcription factor LbUBC positively regulates salt gland development and salt tolerance by directly binding to the LbTTG1 promoter and repressing its transcription.

KEY MESSAGE：: LbUBC enhances salt tolerance by promoting salt gland development via repressing LbTTG1, revealing a synergisticregulatory mechanism in Limonium bicolor. In the context of increasingly severe soil salinization, salt-tolerant genetic resources from halophytes show great application potential. In particular, the recretohalophyte Limonium bicolor, which possesses specialized salt gland structures, has become a key model for deciphering the molecular mechanisms underlying salt tolerance and salt gland development. In this study, using LbTTG1-overexpressing and -silenced lines, we demonstrate that LbTTG1 negatively regulates salt-gland development and salt tolerance. Through yeast one-hybrid, EMSA, and dual-luciferase assays, Lb7G33228 (LbUBC) was screened and verified as an upstream transcriptional regulator of LbTTG1. LbUBC enhances salt tolerance in L. bicolor by positively regulating salt-gland development, verified using LbUBC silence and overexpression strains. Interestingly, LbUBC represses the expression of its downstream target LbTTG1, thereby releasing the inhibitory effect of LbTTG1 on salt-gland development. In this manner, LbUBC positively regulates salt-gland development, achieving a dynamic balance in the regulation of salt-gland development and salt tolerance in L. bicolor. This study reveals a synergistic regulatory mechanism involving multiple genes, offering new insights for comprehensively dissecting the molecular regulatory network of salt-gland development.

Salt Tolerance↗

PubMed1991

Absence of the Staub-Traugott effect in endotoxicosis.

Intravenous glucose tolerance tests (IVGTTs) using 1.2 g/kg of D-glucose in fasted, male rats were repeated twice, with an interval of 75 min, during early (2.5 hr) and late (26.5 hr) nonlethal endotoxicosis induced by Salmonella enteritidis endotoxin (ETX) at 10 micrograms/kg i.v. In comparison with saline controls, glucose tolerance was dramatically increased in early endotoxicosis; however, it was restored to near normal in late endotoxicosis. Augmentation of tolerance by repeated IVGTTs i.e. the Staub-Traugott effect, occurred in the saline control groups; however, it was absent in both early and late endotoxicosis. The elevations of plasma insulin (IRI) in response to the glucose loads were exaggerated vs. controls in both early and late endotoxicosis; however, the hyperinsulinemias were not significantly diminished by repeated IVGTTs in any group. These results indicate loss of the Staub-Traugott effect in endotoxicosis that is 1) independent of augmented insulin secretory responses to a repeated glucose challenge and 2) dependent on some adaptive cellular mechanisms to repeated glucose loads which were impaired in nonlethal endotoxicosis.

Animals↗

PubMed1995

A role for nitric oxide in X-ray contrast material toxicity.

RATIONALE AND OBJECTIVES: We assessed the role that nitric oxide (NO) plays in contrast media (CM) toxicity, using 100% lethal dose (LD100) studies in hyperimmune Brown Norway (BN) rats. METHODS: Ninety-two BN rats and 41 Sprague-Dawley (SD) rats underwent CM LD100 tail vein injections with methylglucamine iothalamate or sodium iothalamate to the point of cessation of respiration. Methylglucamine hydrochloride also was injected. The injections were accompanied by L-arginine (L-Arg) or D-arginine (D-Arg) analogues or by an H1 blocker. L-Arg analogues inhibit NO formation, and D-Arg analogues do not. RESULTS: An L-Arg analogue, but not a D-Arg analogue, increased the tolerance of BN rats (p < .005) for methylglucamine iothalamate but not for sodium iothalamate. The L-Arg analogue also protected BN rats against methylglucamine chloride injections (p < .002). H1 blockade protected BN rats against methylglucamine iothalamate (p < .0005) and methylglucamine chloride (p < .005) injections. None of these measures altered the CM tolerance of SD rats. In SD rats, injections of either methylglucamine iothalamate or sodium iothalamate along with a D-Arg analogue or normal saline were better tolerated than similar injections in BN rats (p < .01 and .002 for methylglucamine iothalamate and sodium iothalamate, respectively). In SD rats but not BN rats, sodium iothalamate was better tolerated than was methylglucamine iothalamate (p < .0005). CONCLUSION: NO appears to play a significant role in BN rats LD100 CM toxicity and has been implicated by others in the blood pressure fall characterizing some forms of antigen-induced anaphylaxis [1, 2]. The results of the current study and the literature suggest that methylglucamine-modulated release of histamine from mast cells may underlie the NO production.

Anaphylaxis↗