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1.
A method is described for the demonstration of ATPase, Cholinesterase and acid phosphatase activity in thin sections of mosquito larvae fixed in 1:9 v/v mixture of acetone and 10% neutral buffered formalin and embedded in hydroxyethyl methacrylate (HEMA). ATPase activity, observed as a black brown precipitate, was found in the brush border of gastric caeca and microvilli of columnar epithelial cells of the hind gut and Malpighian tubules. Some basal cell membrane activity could also be seen. Cholinesterase activity was found in thoracic and abdominal ganglia. The reaction product had a fine particulate appearance and predominated in the axonal processes. Azo dye reaction product indicative of acid phosphatase activity was found in the epithelial cells of the midgut and gastric caeca. Lysosomal and extra-lysosomal activity was observed, the larger secondary lysosomal sources predominating in the perinuclear region. The fixation regime and embedding procedure outlined has enabled a sub-cellular localization of enzymatic activities which is superior to that obtainable with conventional procedures.  相似文献   

2.
The properties and localization of ATPase system in nuclei of skeletal muscle of normal rabbit and of those with experimental muscle dystrophy were studied by electron cytochemistry. The product of cytochemical reaction of ATP hydrolysis, which is a marker of ATPase activity localization in nuclear ultrastructures, was detected on the nuclear membrane, in chromatin and in the nucleolus, ATPase activity in the nuclei was detected in the presence of both, Mg2+ and Ca2+. Addition to the incubation medium, originally containing Mg2+, Na+ and K+, resulted in an increased formation of the product reaction in all the nuclear ultrastructures in both in the norm and under experimental muscle dystrophy. However, specific inhibitor of Mg2+, Na+, K+-ATPase--ouabain--suggests the absence in the nuclei of skeletal muscles of rabbit of transport ATPase working in the "Na-pump" system. The results of experiments with a specific complex of Ca2+--EGTA allow to suppose that Mg2+, Ca2+-ATPase of skeletal muscle nuclei of normal rabbits is localized in the nucleoplasm, whereas Mg2+-ATPase is found on the nuclear membrane. Using EGTA we failed to detected the localization of Mg2+, Ca2+-ATPase in nuclear ultrastructures upon experimental muscular dystrophy.  相似文献   

3.
The cytochemical localization of ATPase in differentiating and mature phloem cells of Pisum sativum L. has been studied using a lead precipitation technique. Phloem transfer cells at early stages of differentiation exhibit strong enzyme activity in the endoplasmic reticulum (ER) and some reaction product is deposited on the vacuolar and plasma membranes. As the phloem transfer cells mature and develop their characteristic wall structures, strong enzyme activity can be observed in association with the plasma membranes and nuclear envelopes. Mature phloem transfer cells with elaborate cell-wall ingrowths show ATPase activity evenly distributed on plasma-membrane surfaces. Differentiating sieve elements show little or no enzyme activity. When sieve elements are fully mature they have reaction product in the parietal and stacked cisternae of the ER. There is no ATPase activity associated with P-protein at any stage of sieve-element differentiation or with the sieve-element plasma membranes. It is suggested that the intensive ATPase activity on the plasma membranes of the transfer cells is evidence for a transport system involved in the active movement of photosynthetic products through these cells.Key to labeling in the figures ER endoplasmic reticulum - P parenchyma cell - PP P-protein - SE sieve element - SPP sieve-plate pore - TC transfer cell  相似文献   

4.
This investigation deals with the localization of sites of ATPase activity, especially of transport ATPase, in nerve fibers of the squid Doryteuthis plei, at the subcellular level. Splitting of ATP liberates inorganic phosphate which reacts with lead to form a precipitate in the tissue. The reaction was made on nerve fibers fixed with glutaraldehyde. Frozen slices were incubated in Wachstein-Meisel medium containing ATP and Pb(NO3)2. Deposits of reaction product were found in the axolemma (towards its axoplasmic side), Schwann cell membranes (mainly at the channels crossing the layer), and mitochondria. Control experiments revealed that no deposits were observed in nerve fibers fixed in osmium tetroxide prior to incubation in the medium containing ATP, or in nerve fibers incubated without substrate or with adenosine monophosphate, adenosine diphosphate, glycerophosphate, or guanosine triphosphate as substrate. For evaluation of transport ATPase activity, these findings were compared with results obtained with nerve fibers treated with G-strophanthin or K-strophanthoside before or after glutaraldehyde fixation. The cardiac glycosides produced a disappearance or diminution of the deposits. The largest inhibitory effect was observed in the axolemma. The findings indicate that the highest ATPase activity is localized in the axolemma and may be due primarily to transport ATPase.  相似文献   

5.
K J Chacko 《Acta anatomica》1977,97(4):379-386
Timed pregnancies were obtained in Sprague-Dawley rats, and cardiac tissues from embryos of days 10, 11, 12, 13, 14 and from newborn rats were used for the cytochemical localization of ATPase activity utilizing a lead phosphate precipitation procedure. Following incubation with ATP as the substrate, granular deposits of reaction product are discernible on the cell membranes of the embryonic myocardium. There is a noticeable decrease in the intensity of reaction product as visualized in the electron micrographs from the 10th day of gestation to the 14th day. No granular reaction product is recognizable in myofibrils, mitochondria or other organelles in the cytoplasm. It appears that there is a selective deposition of the reaction product on the cell membranes or structures derived from it. The intense ATPase activity seen on 10th and 11th days seems to be correlated with the initial appearance of myofilaments and fibrils in the myocardial cells.  相似文献   

6.
The sites of reaction product resulting from ATPase and 5-nucleotidase activities remaining in parenchymatous cells of osmium-fixed rat liver were studied by electron microscopy of thin sections. These indicate that both ATPase and 5-nucleotidase activities are localized in the plasma membrane where it folds to form the microvilli of the bile canaliculus, and that 5-nucleotidase activity is also present in the microvilli at the sinusoidal aspects of the cells. It is suggested that these enzymes, particularly ATPase, may play a role in molecular transport or in some kind of membrane activity at the cell surface. Of special interest is the apparent differential localization of these enzymes at the absorptive and secretory regions of the plasma membrane of the cell. It may be of interest to study changes in these enzyme localizations in pathologic states, as a sign of changed cell function. Some of the difficulties in the interpretation of enzyme reaction products seen in electron micrographs are discussed.  相似文献   

7.
Alkaline phosphatase (AP), 5'-nucleotidase (5'N), Mg2+-activated ATPase (Mg-ATPase) and Ca2+-activated ATPase (Ca-ATPase) were studied in sychronized HeLa S3 cells with cytochemical methods and electron microscopy. It was found that AP activity, as determined by the deposition of lead phosphate reaction product (r.p.) was most active in mitotic (M), early and middle G1 cells, less active in late G1 and almost undetectable in S phase cells. Most AP enzyme activity was found to be associated with undulations (mainly microvilli) of the plasma membrane. Fluctuations and the redistribution of 5'N were also observed; the reaction for 5'N was positive in all phases of the cell cycle studied, it was strongest in M cells and in the majority of middle G1 cells. Mg-ATPase activity was present in the plasma membranes of cells throughout the cell cycle, but did not show noticeable fluctuations in activity and distribution. Ca-ATPase activity appeared in plasma membranes and in limited areas of cell nuclei but was evident only in S phase cells. The results of the present study confirm and extend previous biochemical observations and indicate that changes in membrane phosphate activities are associated with enzyme activity redistributions within the plasma membrane during the HeLa S3 cell cycle.  相似文献   

8.
Synopsis ATPase activity in the developing first mandibular molar of the mouse was demonstrated at the electron microscopic level with the method of Wachstein & Meisel (1957). It was localized along the cell surfaces of the ameloblast and stratum intermedium interface, the stratum intermedium and the stellate reticulum. The ATPase final reaction product was also present at the cell membranes of the proximal region of adjacent ameloblasts and extended to the level of the nuclei. The demonstration of ATPase mainly on the plasma membranes was similar to the observations by other investigators of various non-odontogenic cell types involved in the exchange of materials across plasma membranes.  相似文献   

9.
Filipin was used as cytochemical probe for sterol detection in freeze-fractured prostate nuclear membranes from rats under different hormonal conditions. Isolated prostate acini and nuclei were fixed in glutaraldehyde and post-treated with filipin, according to Robinson and Karnovsky (1980). In general, most plasma and intracellular cytoplasmic membranes displayed a marked response to filipin in either epithelial and stromal cells from normal and castrated animals. Nuclear membranes from epithelial secretory cells were systematically negative to filipin labeling in normal animals, although after castration a positive response was detected. Stromal nuclear membranes were labeled both in normal and castrated animals. Filipin-treated isolated nuclei displayed the same overall labeling pattern but there was a different distribution of induced deformations relative to intact cell nuclei. These observations indicate that: a) nuclear membranes from different cell types have different responses to filipin; b) a change in the molecular organization of nuclear membranes from prostate secretory cells follow castration; c) nuclei isolation affects the distribution of filipin induced deformations on the membranes.  相似文献   

10.
The effects of several cationic polymers (poly-L-lysines, protamine, and histone) on rabbit gall bladder epithelial cells were studied to explore possible roles for negative sites in the membrane. The tissue was bathed for 30 min at 37°C in Ringer''s solutions containing from 0.1 to 100.0 µg/ml of cationic polymers, and subsequently was fixed with 1% OsO4 and examined with the electron microscope. All cationic polymers, at appropriate concentrations, produced similar changes in membrane structure. Adjacent membranes frequently were fused. Membrane structures such as microvilli lost rigidity. Cell membranes showed an apparent increase in permeability as judged by osmotically traumatized cells. These results indicate that fixed anionic sites play significant roles in stabilizing epithelial membrane structures.  相似文献   

11.
Cultures of normally proliferating Hela cells have been examined in thin sections by electron microscopy following glutaraldehyde fixation, staining in Wachstein and Meisel's adenosine triphosphate containing medium, postosmication, and embedding in an epoxy resin. The cells were stained in suspension in order to ensure uniform accessibility to reagents. Discrete localization of the enzyme reaction product (lead phosphate) was found at the plasma membranes of about half the cells, but nowhere else. It appeared in the form of an intensely electron-opaque deposit lying close against the outer surface of the cells and varying in amount from a chain of small particles to a dense band about 30 mµ in width. This opaque reaction product was present over microvilli when absent elsewhere on a cell, was heaviest where microvilli and processes were profuse, and was minimal or lacking where cell surfaces were smooth. These observations are discussed in relation to both the idea that surface enzyme activity varies with the physiological phase of individual cells in a population, and the problem of how such enzyme activity becomes manifest at a given site on a morphologically changing membrane system.  相似文献   

12.
小麦珠心细胞衰退过程中ATP酶的超微细胞化学定位   总被引:12,自引:1,他引:11  
采用磷酸铅沉淀技术对小麦(Triticum aestivum )珠心细胞衰退过程进行了ATP酶的超微细胞化学定位。初始衰退的珠心细胞,ATP酶只定位于细胞膜上,其它部位未见有ATP酶活性。衰退中期的珠心细胞,细胞膜上ATP酶活性减弱并逐渐消失;细胞核染色质和细胞质中一些细胞器上存在ATP酶活性。在严重衰退的珠心细胞中,只在细胞核染色质上存在ATP酶活性。珠心细胞的细胞核以两种方式衰退。衰退的细胞核染色质碎片仍存在ATP酶活性,并向胚囊方向转移。推测小麦珠心细胞衰退过程中细胞膜上ATP酶变化反映了珠心细胞生理状态转变;细胞核染色质上ATP酶与其形态变化和运动等有关  相似文献   

13.
Ultracytochemical localization of ATPase activity was carried out using a lead phosphate precipitation technique in the nucellar cells of wheat during degeneration. ATPase was only localized on the plasma membranes of nueellar cells at the. early degenerative stage, then decreased and disappeared at the mid-degenerative stage. Meantime it was also observed in the nuclear chromatin and some cytoplasmic organelles. ATPase activity was only observed in the nuclear chromatin in the extremely degenerated nucellar cells. Two patterns of unclear degeneration was found in the degenerated nucellar cells. A lot of small fragments with ATPase from the degenerated nuclei moved toward the embryo sac. It is suggested that the change of ATPase activity on the plasma membranes is related to the physiological change of nucellar cells, and that in the nuclear chromatin is associated with the stages movement of chromatin during the process of nucellar cells degeneration.  相似文献   

14.
V A Agafonov 《Tsitologiia》1976,18(12):1479-1483
A localization of ATPase activity in a rat's brain was studied by the lead method at the presence of Mg2+. The highest activity was noticed in the capillar basal layer, in nucleoli and nuclear chromatin. Less intensive sedimentation of precipitate was observed on the external nuclear membrane, granular cytoplasmic reticulum, ribosomes and in lipofuscin granules. Besides, the reaction product was observed on the cytomembrane of neurons, in synaptic slits and on the vesicles of some terminals. No ATPase activity was seen in mitochondria in the experimental conditions. Equal distribution of reaction product was seen in the cortex and hypothalamus.  相似文献   

15.
Studies of ultrastructure and ATPase localization of the mature embryo sac in Vicia faba L. show that the egg cell has no cell wall at thechalazal end, it has a chalazally located nucleus and a large micropylar vacuole. There are many nuclear pores in the nuclear membrane. The cytoplasm is restricted around the nucleus. Dictyosome and mitochondria are few. There are some starch grains and lipid grains in the egg cytoplasm. There are no obvious differences between two synergids. No cell wall is seen at the chalazal end either, but there are some vesicles which project to vacuole of the central cell and fuse with its vacuolar membrane. Plasmodesmata connections occur within the synergid wall where it is adjacent to the central cell. The synergid has a micropylarly located nucleus and a chalazal vacuole, the nucleus is irregularly shaped. The synergid cytoplasm is rich in organelles. The filiform aparatus is of relatively heterogeneous structure. The central cell is occupied by a large vacuole and its cytoplasm is confined to a thin layer along the empryo sac wall, but is rich in various organelles, starch grains and lipid bodies. Nucleolar vacuoles are often present two polar nuclei. The nuclear membranes of two polar nuclei have partly fused. ATPase reactive product was located obviously at the endoplasmic reticulum in cytoplasm of the egg cell and central cell. The embryo sac wall consists of different density of osmiophilic layer. There are some wall ingrowths in chalazal region of the embryo sac. The long-shaped and cuneate cells of chalazal region are peculiar. Special tracks of ATPase reactive products are visible at their intercellular space which may be related to transportation of nutrients.  相似文献   

16.
The ultrastructural localization of adenosine tripkosphatase (ATPase) activity in cotyledon cells of tomato was carried out by use of the cytochemical method of lead phosphate precipitation, and the changes in ATPase activity during chilling stress of the tomato seedlings were studied. The following experimental results have been obtained: 1. The ATPase activity in the cotyledon cells of tomato seedlings germinated and grown at 28 ℃. was located at plasmolemma, plasmodesmata, nucleoli and nuclear chromatin chloroplast lamellae, many sites of cell wall, and the surface of cell wall bordering the intercellular spaces and their inclusions. 2. When the tomato seedlings were subjected to chilling treatment for 4 h. at 5 ℃., the ATPase activity in cotyledon cells was indifferent from that of non-chilling treated seedlings. After chilling treatment for 12 h. at 5 ℃., the reaction of ATPase activity at plasmolemma, and in cell wall and intercellular spaces was markedly reduced. though the high activity reaction of ATPase in nuclei and at chloroplast lamellae was still maintained. When the tomato seedlings were subjected to chilling stress for 24 h. at 5℃., the ATPase activity at plasmolemma and in cell wall was almost inactivated, while the ATPase activity in nuclei and at chloroplast lamellae was only slightly lowered. These results indicated that the chilling injury may influence firstly on the ATPase activity of cell surface (plasmolemma and cell wall). 3. The role of intercellular spaces used as the passage of materials and the process and mechanism of chilling injury are discussed.  相似文献   

17.
c-erbB receptors are usually located in cell membranes and are activated by extracellular binding of EGF-like growth factors. Unexpectedly, using immunofluorescence we found high levels of c-erbB-3 within the nuclei of MTSV1-7 immortalized nonmalignant human mammary epithelial cells. Nuclear localization was mediated by the COOH terminus of c-erbB-3, and a nuclear localization signal was identified by site-directed mutagenesis and by transfer of the signal to chicken pyruvate kinase. A nuclear export inhibitor caused accumulation of c-erbB-3 in the nuclei of other mammary epithelial cell lines as demonstrated by immunofluorescence and biochemical cell fractionation, suggesting that c-erbB-3 shuttles between nuclear and nonnuclear compartments in these cells. Growth of MTSV1-7 on permeable filters induced epithelial polarity and concentration of c-erbB-3 within the nucleoli. However, the c-erbB-3 ligand heregulin beta1 shifted c-erbB-3 from the nucleolus into the nucleoplasm and then into the cytoplasm. The subcellular localization of c-erbB-3 obviously depends on exogenous stimuli and on the stage of epithelial polarity and challenges the specific function of c-erbB-3 as a transmembrane receptor protein arguing for additional, as yet unidentified, roles of c-erbB-3 within the nucle(ol)us of mammary epithelial cells.  相似文献   

18.
ADENOSINE TRIPHOSPHATASE LOCALIZATION IN AMPHIBIAN EPIDERMIS   总被引:16,自引:10,他引:6       下载免费PDF全文
The localization of ATPase1 activity has been studied by light and electron microscopy in the epidermis of Rana pipiens, Rana catesbiana, and Bufo marinus. The reaction was carried out on skin (glutaraldehyde-fixed or fresh) sectioned with or without freezing. Best results were obtained with nonfrozen sections of fixed tissue. The incubation mixture was either a Wachstein-Meisel medium, or a modification which approximates assay systems used in biochemical studies of transport ATPases. The reaction product was found localized in contact with the outer leaflet of all cell membranes facing the labyrinth of intercellular spaces of the epidermis. It was absent from: (a) membrane areas involved in cell junctions (desmosomes, zonulae and maculae occludentes); (b) cell membranes facing the external medium (i.e., those on the distal aspect of the ultimate cell layer in s. corneum); (c) cell membranes facing the dermis (those on the proximal aspect of cells in s. germinativum). In the presence of (Na+ + K+) the localization did not change, but the reaction was not appreciably activated. A similar though less intense reaction was obtained with ITP, but not with ADP, AMP, and GP as substrates. The results are discussed in relation to available data on transport ATPases in general, and on the morphology and physiology of amphibian skin in particular. Assuming that the ATPase studied is related to transport ATPase, the findings suggest a series of modifications to the frog skin model proposed by Koefoed-Johnsen and Ussing. The salient feature of this modified model is the localization of the Na+ pump along all cell membranes facing the intercellular spaces of the epidermis.  相似文献   

19.
The localization of Mg-stimulated ATPase activity was determined in the sensomotor cortex mitochondria of Wag rats after aminazin administration (15 mg/kg). Apart from normal mitochondria containing no reaction product, a number of altered mitochondria with different localization in them of the ATPase reaction product were recorded. The intact animals showed no sediment in the mitochondria. It is suggested that aminazin-induced increase in ATP-hydrolase activity is caused by two factors: neuroleptic-induced decrease in glycolytic and oxidative cell activity and increased permeability of mitochondrial membranes.  相似文献   

20.
Radioactivity, apparently in cytonucleoproteins, from an amino acid-labeled nucleus implanted into a non-radioactive cell appeared in the host nucleus within 10 minutes, and the typical equilibrium ratio 70:30 donor nucleus radioactivity:host nucleus radioactivity was reached in 4 to 5 hours at 25°C. If such binucleates grew and divided, no localization of radioactivity was observable in cells fixed during mitosis, but the protein label remained concentrated in the daughter interphase nuclei for at least 4 generations. Continued migration of cytonucleoproteins was observed if these daughter nuclei were transplanted to other unlabeled cells. The Q10 (19° to 29°C) of the migration rate of radioactive cytonucleoproteins was ca. 1.3, suggesting that passage through the cytoplasm occurred by diffusion. Both non-migratory nuclear proteins and cytonucleoproteins appear to be synthesized in the cytoplasm.  相似文献   

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