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1.
Qualitative and quantitative composition of fatty acids (FA) in the lipids of vegetative organs of the halophyte Suaeda altissima (L.) Pall. grown at different NaCl concentrations in nutrient solution was studied. Along with this, the biomass of these organs, the content of water and Na+, Cl?, and K+ ions in them, and the ultrastructure of root and leaf cells were determined. At both low (1 mM) and high (750 mM) NaCl concentrations in nutrient solution, plants could maintain growth and water content in organs, demonstrating a noticeable increase in the dry weight and a slight increase in the water content at 250 mM NaCl. At all NaCl concentrations in nutrient solution, S. altissima tissues contained a relatively high K+ amount. Under salinity, Na+ and Cl? ions contributed substantially into the increase in the cell osmotic pressure, i.e., a decrease in their water potential; in the absence of salinity, K+ fulfilled this function. In the cells of both roots and leaves, NaCl stimulated endo- and exocytosis, supposedly involved in the vesicular compound transport. 750 mM NaCl induced plasmolysis and changes in the membrane structure, which can be interpreted as degradation processes. Under optimal NaCl concentration in medium (250 mM), the content of lipids in plant aboveground organs per fresh weight was more than 2.5-fold higher than under 1 or 750 mM NaCl, whereas in the roots opposite patten was observed. When plants were grown under non-optimal conditions, substantial changes occurred in the qualitative and quantitative FA composition in lipids of both aboveground organs and roots. Observed changes are discussed in relation to processes underlying S. altissima salt tolerance and those of disintegration occurring at the high external NaCl concentration (750 mM).  相似文献   

2.
7.5%氯化钠溶液对失血性低血压狗升压作用的中枢机制   总被引:2,自引:0,他引:2  
郑惠珍  刘锡仪 《生理学报》1994,46(4):338-346
9对狗作头部交叉循环,4对狗作脑交叉循环后,股动脉失血使平均动脉压(MAP)降至5.33kPa左右,维持30min。从其中一只狗(A狗)股静脉输入占总失血量10%的7.5%NaCl溶液(实验组),或生理盐水(对照组);另一只狗(B狗)不作任何处理。结果:实验组A,B两狗动脉血压(AP)均显著回升,并维持至输液后60min,其中收缩压(SP)回升幅度大于舒张压(DP),脉压(PP)加大。对照组AP回升值无统计学意义。实验组及对照组心率(HR)均无明显变化。动脉血红细胞比容皆下降,但其下降值组间比较,P>0.05。实验组A狗血浆钠有意义地增高,P<0.01;B狗变化同对照组。结果提示:在7.5%NaCl溶液恢复失血性低血压的作用机制中,中枢神经系统起重要作用。  相似文献   

3.
Deoxycorticosterone pivalate (2.5 mg/kg) given intramuscularly on four occasions 10-15 days apart over a period of 45 days to unilaterally nephrectomized adult male mongrel dogs, receiving as drinking solution 0.9% NaCl in 5% dextrose, resulted in an average sustained rise in the mean arterial blood pressure of 30 mm Hg (1 mm Hg - 133 N/m2) in 60% of the animals. Hypertensive dogs had in their arterial tissues generally more sodium, potassium, magnesium, and calcium than the similarly treated but non-hypertensive dogs, but compared to the tissues of operated untreated or unoperated normotensive dogs, only sodium and calcium were significantly higher. The dogs who were similarly treated but did not develop hypertension had in their arterial tissues less sodium, potassium, and magnesium than operated untreated or unoperated normotensive dogs. Norepinephrine content in the branches of mesenteric arteries of all deoxycorticosterone- and NaCl-treated animals, irrespective of their blood pressure, was significantly lower, and in the myocardium significantly higher, than either the unoperated normotensive or operated but not further treated dogs. It is concluded, therefore, that in deoxycorticosterone + NaCl treatment the dogs which developed hypertension had more arterial sodium, potassium, magnesium, and calcium than those who were similarly treated but remained within the limits of normal blood pressure, and that there was no difference between hypertensive and non-hypertensive dogs in regard to their cardiovascular norepinephrine content.  相似文献   

4.
Dekanski's method was used to estimate the pressor activity of the extracts of the posterior pituitary lobe in anaesthetized rats, after the infusion of 0.9% NaCl solution above the supraoptic nuclei and haemorrhage in the amount of 1.5% of body weight or after the infusion of Substance P solution above the supraoptic nuclei and haemorrhage. It has been found that the vasopressin content in the posterior pituitary lobe decreased about 20% after the infusion of 0.9% NaCl solution and haemorrhage. The infusion of Substance P above the supraoptic nuclei inhibits the loss of vasopressin from the pituitary caused by haemorrhage.  相似文献   

5.
The anal organ of larvae of the wild type and the mutant ‘lethaltranslucida’ (l(3)tr, 3–20±0·8) of Drosophila melanogaster was studied by electron microscopy. By means of cryoscopy and microtitration the total osmotic concentration and the chloride content of the haemolymph were also determined. In addition, the effects of hypotonic and hypertonic solutions on the anal organs and the haemolymph concentration have been analysed in detail. We were especially interested in the functional significance and a possible disturbance of these anal organs in the lethal mutant.On the basis of the following characters the anal organ appears as a typical absorption organ: (a) The cuticle is distinctly thinner than that of the remaining body parts and has an enlarged surface by forming numerous porous infoldings. (b) On the cuticular surface the plasma membrane of the singlelayered epidermal cells forms a large number of folds oriented parallel to each other, resulting in a further increase of the absorption surface. (c) An extensive network of microtubules and a dense population of mitochondria, vacuoles, and vesicles in the cytoplasm suggest that an active transport process takes place in this organ.After 1 hr in a strong hypotonic solution (distilled water) the plasma membrane folds of both +/+ and l(3)tr larvae increase and penetrate deeper into the epidermal cell. The mitochondria also increase in number and are located between the apical folds. Conversely, in a hypertonic solution (1·42–11·96% NaCl) the plasma membrane folds become shorter and fewer in number. The mitochondrial density decreases. With increasing salinity and duration various unidentified bodies, degenerated mitochondria, and vesicles appear, indicating the beginning of autolysis.The osmotic concentration of 4-day-old +/+ larvae is found to be 1·02% NaCl, whereas that of l(3)tr larvae of a corresponding physiological age (5 days old) amounts to only 0·65% NaCl. Both genotypes are able to regulate the osmotic concentration in a hypotonic solution; the upper limit of salt concentration of the surrounding medium for a successful regulation is 5 per cent.The chloride concentration of +/+ larvae aged 4 days is found to be 0·19% NaCl, and that of l(3)tr larvae of a corresponding physiological age 0·14% NaCl. In a hypotonic solution both genotypes are capable of regulating the chloride concentration. However, this fails in a hypertonic medium with a concentration higher than 1% NaCl. When the anal organs are blocked by AgNO3 impregnation, the regulatory ability breaks down completely. No distinct difference in the fine structure as well as in the regulatory achievement of the anal organs between the wild type and the l(3)tr mutant could be detected. It seems that the mutational effect does not lie primarily in a defect of the water balance.  相似文献   

6.
White goosefoot plants (Chenopodium album L. of the family Chenopodiaceae) grown at various NaCl concentrations (3–350 mM) in the nutrient solution were used to study the cell ultrastructure as well as the qualitative and quantitative composition of fatty acids in the lipids of vegetative organs. In addition, the biomass of Ch. album vegetative organs, the water content, and the concentrations of K+, Na+, and Cl were determined. The growth rates of plants raised at NaCl concentrations up to 200–250 mM were the same as for the control plants grown at 3 mM NaCl; the growth parameters remained rather high even at NaCl concentrations of 300–350 mM. The water content in Ch. album organs remained high at all NaCl concentrations tested. Analysis of the ionic status of Ch. album revealed a comparatively high K+ content in plant organs. At low NaCl concentrations in the nutrient solution, K+ ions were the dominant contributors to the osmolarity (the total concentration of osmotically active substances) and, consequently, to the lowered cell water potential in leaves and roots. As the concentration of NaCl was increased, the plant organs accumulated larger amounts of Na+ and Cl, and the contribution of these ion species to osmolarity became increasingly noticeable. At 300–350 mM NaCl the contribution of Na+ and Cl to osmolarity was comparable to that of K+. An electron microscopy study of Ch. album cells revealed that, apart from the usual response to salinity manifested in typical ultrastructural changes of chloroplasts, mitochondria, and the cytosol, the salinity response comprised the enhanced formation of endocytic structures and exosomes and stimulation of autophagy. It is supposed that activation of these processes is related to the removal from the cytoplasm of toxic substances and the cell structures impaired by salt stress conditions. The qualitative and quantitative composition of fatty acids in the lipids of Ch. album organs was hardly affected by NaCl level. These findings are consistent with the high salt tolerance of Ch. album, manifested specifically in retention of growth functions under wide-range variations of NaCl concentration in the nutrient solution and in maintenance of K+, Na+, and Cl content in organs at a constant level characteristic of untreated plants.  相似文献   

7.
Acatalasemic Beagle dogs which were maintained in our laboratories showed no sign of catalase activity at all in the erythrocytes, and glutathione peroxidase and superoxide dismutase were at normal levels. Immunoblotting analysis demonstrated that no catalase protein is detectable in their erythrocytes. On the other hand, catalase activity was detected in other tissues and organs, albeit at varying, lower levels than in normal dogs. Quantitative immunoblotting analysis consistently demonstrated that the catalase protein is expressed in the liver and kidneys of acatalasemic dogs in proportion to the activity in these organs. The catalase mRNA expressions in the blood, liver and kidneys in acatalasemic dogs were almost the same as those in normal dogs. These results suggested that catalytically normal catalase protein is translated from mRNA in the tissues and organs including erythrocytes, but in erythrocytes this enzyme protein is disposed of by an unknown mechanism.  相似文献   

8.
NaCl处理对空心莲子草营养器官解剖结构的影响   总被引:1,自引:0,他引:1  
利用光学显微技术,对不同浓度NaCl处理后的空心莲子草的营养器官进行形态解剖学研究。结果表明:不同浓度的NaCl处理下生长的空心莲子草解剖结构与对照相比发生了显著变化,这些变化表现为:随着盐浓度的逐渐增加,叶片面积变小而厚度增加;茎的横向生长受抑制;角质膜进一步增厚;营养器官的通气组织进一步发达,根、茎、叶中的胞间隙或孔隙紧密相连,使植物体上下贯通进行气体交换;根中的木栓细胞层数增加。  相似文献   

9.
The effects of pH, ionic strength, stain concentration, magnesium concentration, and various fixative agents on DNA staining with the fluorescent antibiotics olivomycin, chromomycin A3, and mithramycin were examined with DNA in solution and in mammalian cells. Ethanol-fixed Chinese hamster cell populations (line CHO) stained with mithramycin and analyzed by flow cytometry provided DNA distribution patterns with a high degree of resolution. Glutaraldehyde-fixed cells exhibited about one-half the fluorescence intensity of ethanol-fixed cells; however, the percentages of cells in G1, S, and G2 + M were comparable. DNA distributions obtained for formalin-fixed cells were unacceptable for computer analysis. Cell staining over a pH range of 5-9 in solutions containing 0.15-1 M NaCl and 15-200 mM MgCl2 provided optimal results based on the DNA profiles obtained by flow cytometry. The intensity of cells stained in 1 M NaCl was one and one-half times greater than cells stained in the absence of NaCl; however, spectrophotofluorometric analysis of mithramycin-magnesium-DNA complexes in solution revealed no significant changes in fluorescence intensity over a range of 0-1.75 M NaCl. These results and those obtained by flow cytometry analysis indicate that the increase in fluorescence of stained cells as a function of increasing ionic strength is due to changes in chromatin structure, providing a larger number of binding sites for the dye-magnesium complex.  相似文献   

10.
The affinity of olfactory receptors in fish for trypan blue as a vital stain is similar to that in amphibia and mammals. But, so far, only Ictalurus has given satisfactory staining. After anesthetizing the animals with MS 222 (tricaine methane sulfonate), the olfactory folds were laid bare by excising the flap of skin between anterior and posterior nares. Next, filter paper was employed to absorb the water and mucus between the folds which were then covered with staining solution. The variations in the treatment were: (a) exposure to 0.5, 1.0 and 2.0% stain concentration, (b) use of distilled water or of 0.7% NaCl solution, (c) staining times of 20, 40, 60 and 80 min. The treated tissues were fixed in Heidenhain's SUSA for 12 hr, dehydrated in isopropyl alcohol, and embedded by passage through methyl benzoate and benzene into paraffin. The sections were cut at 7 μ and mounted in Canada balsam. Vital staining in a 1% distilled water solution for 60 min gave the best results. The receptors were deep blue and contrasted well with the supporting cells. Also, the central receptor-cell processes had taken the stain. Preparations exposed longer than 60 min showed a loss of stain from the receptors. In Ictalurus all receptors are spindle-shaped with peripheral processes of little varying length and thickness depending on the depth of their nuclei within the epithelium. Most nuclei lie near the center of the epithelium. The central processes are thinner (0.25-0. 28 μ) and more curved than the peripheral ones (0.7-0. 9 μ) and may contain small pale blue apparently vesicular swellings. Trypan blue delimits receptor cells more sharply than silver impregnation and seems to be well suited for studies of comparative histology and cytology of vertebrate olfactory epithelium. Methylene blue vital staining of the same tissue shows selectivity for the intraepithelial bundles of central receptor processes rather than for the receptor nuclei.  相似文献   

11.
The described technique, based upon a one-step Mallory-Heidenhain stain, can be applied as a routine stain for glutaraldehyde or OsO4 fixed, Epon embedded tissues of various organs. The technique consists of a short treatment of the sections with H2O2, a nuclear staining with celestine blue B and a final staining in a modified Cason's solution. The different tissue and cell components are displayed as follows: dark brown nuclei, yellow cytoplasm, red collagen fibers and blue elastic fibers. Intracytoplasmic components as glycogen and mucus are stained respectively blue and violet, whereas other inclusions such as leucocyte granules are colored orange to red.  相似文献   

12.
The described technique, based upon a one-step Mallory-Heidenhain stain, can be applied as a routine stain for glutaraldehyde or OsO4 fixed, Epon embedded tissues of various organs. The technique consists of a short treatment of the sections with H2O2, a nuclear staining with celestine blue B and a final staining in a modified Cason's solution. The different tissue and cell components are displayed as follows: dark brown nuclei, yellow cytoplasm, red collagen fibers and blue elastic' fibers. Intra cytoplasmic components as glycogen and mucus are stained respectively blue and violet, whereas other inclusions such as leucocyte granules are colored orange to red.  相似文献   

13.
Calluses initiated from leaves and seedlings of the mangrove,Bruguiera sexangula, were isolated from the original tissues and subcultured. Effects of NaCl on growth and ion content of each callus were measured. The growth rate of calluses derived from leaves (leaf callus) gradually decreased as the NaCl concentration in the medium increased, while that of calluses derived from seedlings (seedling callus) was highest in the medium containing 100 mM NaCl. Concentrations of Na and Cl in both calluses increased with increasing the NaCl concentration in the culture medium. The concentration of K of leaf calluses greatly decreased at 300 mM NaCl, while the K concentration of seedling calluses decreased only slightly and remained relatively high even in the presence of 300 mM NaCl. Transient treatment of leaf calluses with media containing high concentrations of NaCl frequently induced regeneration of adventitious tissues.  相似文献   

14.
A recessive mutation of Arabidopsis designated sas1 (for sodium overaccumulation in shoot) that was mapped to the bottom of chromosome III resulted in a two- to sevenfold overaccumulation of Na(+) in shoots compared with wild-type plants. sas1 is a pleiotropic mutation that also caused severe growth reduction. The impact of NaCl stress on growth was similar for sas1 and wild-type plants; however, with regard to survival, sas1 plants displayed increased sensitivity to NaCl and LiCl treatments compared with wild-type plants. sas1 mutants overaccumulated Na(+) and its toxic structural analog Li(+), but not K(+), Mg(2)+, or Ca(2)+. Sodium accumulated preferentially over K(+) in a similar manner for sas1 and wild-type plants. Sodium overaccumulation occurred in all of the aerial organs of intact sas1 plants but not in roots. Sodium-treated leaf fragments or calli displayed similar Na(+) accumulation levels for sas1 and wild-type tissues. This suggested that the sas1 mutation impaired Na(+) long-distance transport from roots to shoots. The transpiration stream was similar in sas1 and wild-type plants, whereas the Na(+) concentration in the xylem sap of sas1 plants was 5.5-fold higher than that of wild-type plants. These results suggest that the sas1 mutation disrupts control of the radial transport of Na(+) from the soil solution to the xylem vessels.  相似文献   

15.
It was established that increased mortality was characteristic of newborn mice from females with dystrophic lesions of the renal tissue. The kidneys of newborns from these females had a less relative weight as compared with newborns from healthy mice. Other organs of experimental and control newborns did not differ in their relative weight. Hypertrophy of the tubule cells with the signs of picnosis of nuclei was noted in the kidneys of experimental newborn animals. In two-month-old mice of the experimental and control groups the kidneys and other organs (liver, heart, lungs, spleen) had no substantial distinctions in the relative weight. The concentration of urea in the blood of two-month-old mice from females with injured kidneys under protein load was higher than in control two-month-old mice from females treated with 0,85% solution of NaCl which speaks of decreased resistance of kidneys in the animals of experimental group against pathogenic factors.  相似文献   

16.
17.
A 1% solution of chlorazol fast pink B in 0.9% NaCl can be used like trypan blue to detect virus inclusions and proteinaceous entities in peelings from leaves or thin sections taken from living plant tissue. Like trypan blue, a solution of the pink dye causes somatic nuclei to swell and thus facilitates observation of their structure. The two dyes combine into a beautiful differential bicolored stain. Mix 5 ml of 0.5% trypan blue stock solution with 35 ml of 1% chlorazol pink B in 0.9% NaCl. Stain fresh tissue 1-2 minutes. The combination stain is superior to either dye alone for differentiating virus entities.  相似文献   

18.
In four conscious dogs with chronic gastric and pancreatic Thomas fistulas we studied the effect of 99% pure cholecystokinin-33 (CCK-33) solutions on pancreatic secretion and PP release. CCK-33 was dissolved in 0.154 M NaCl alone or in the same solution containing 1 g per 100 ml dog albumin. The response of pancreatic protein output to increasing doses of CCK-33 (0.5, 1, 2, 4 IDU/kg per h) was significantly (P < 0.05) higher when CCK was dissolved in NaCl with albumin than in NaCl alone. These results were confirmed by measuring CCK immunoreactivity in samples from tips of infusion lines by a gastrin radioimmunoassay. Release of pancreatic polypeptide (PP) following increasing doses of CCK-33 was also significantly (P < 0.05) elevated when CCK was dissolved in an albumin-containing solution. There was a significant (P < 0.02) correlation between plasma concentrations of PP and pancreatic protein output.This study suggests that albumin should be added to CCK-33 solutions to preserve biological activity. The biological effect of CCK-33 may be substantially underestimated if albumin is omitted.  相似文献   

19.
The concentration of plasma glucose in insulin deprived pancreatectomized dogs was decreased from the basal 385 +/- 44 to 65 +/- 12 mg/dL by the infusion of 7 mU X kg-1 X min-1 insulin. During the infusion, the plasma concentration of immunoreactive glucagon (IRG) did not change and hepatic glucose production was decreased. This is in contrast to earlier findings in alloxan diabetic dogs in which plasma IRG decreased in hypoglycaemia. The hypothesis is put forward that, in contrast to pancreatic alpha cells in which the effect of insulin prevails, neither insulin nor a decrease in the ambient concentration of glucose exerts any effect on the secretion of glucagon from extrapancreatic alpha cells.  相似文献   

20.
In vivo sampling of cardiac triglyceride from dogs during ethanol infusion   总被引:2,自引:0,他引:2  
The feasibility of procuring and analyzing cardiac tissue for triglyceride in vivo was tested in anesthetized dogs. Measurements of triglycerides in samples obtained in vitro confirmed: reproducibility of triplicate analyses of the glycerideglycerol moiety of tissue triglyceride (SEM +/- 2.1%), homogeneity in and between ventricles (SEM +/- 1.8%), and agreement between right endocardial triglyceride and left myocardial triglyceride (difference not significant). Seven dogs received ethanol, 15-30 mg/kg/min, and five dogs received glucose or 0.85% NaCl for 2 hr. Cardiac output and filling pressure were measured from the left ventricle and tissue was taken from the right ventricle with a biopsy catheter before and during infusions. Three to four samples were obtained from each dog; the average weight was 14.4 mg and two to three biopsies were required for each sample. In the ethanol group, triglyceride increased after 15 min and continued to rise; the final triglyceride concentration correlated with the infusion rate. In the glucose-saline group, in vivo triglyceride concentration did not change and did not differ from postmortem triglyceride. Cardiac function declined in the ethanol group and was unaffected in the controls. Thus, multiple in vivo measurements of cardiac lipid are practical and safe and show that ethanol infusions cause early and progressive accumulation of triglyceride in heart muscle.  相似文献   

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