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1.
The phenomenon of blebbing has been recorded in cells obtained from a pleural effusion of a patient with a small cell lung carcinoma. The blebbing manifested itself as a sudden ballooning of the cell membrane which then moved around the perimeter of the cell as a sausage-shaped swelling. This was followed by its rapid collapse. The rapidity of the process allowed real time video recordings, not time lapse, and still frames from the recording were photographed. Cells were also viewed using a scanning electron microscope and more detail of the blebs was revealed. Possible functions of cell blebbing are discussed.  相似文献   

2.
WRK-1, a cloned cell line derived from a rat mammary tumour, responds to physiological concentrations of vasopressin and pharmacological concentrations of oxytocin with increased incorporation of [14C]acetate into lipids and increased protein accumulation. The presence of pharmacological concentrations of insulin, which itself is active on the WRK-1 cells, further enhances the effects of the neurohypophysial hormones. Unlike the action of vasopressin on other responsive tissues, the stimulation of acetate incorporation by WRK-1 cells is not observed until 24 h after the addition of the hormone. The lipids synthesized in response to the hormones are predominantly polar lipids, rather than the triclyclycerold characteristic of the differentiated mammary gland. [1-Deaminocysteine, 8-D-arginine] vasopressin, a vasopressin analogue that lacks pressor activity, has no effect on WRK-1 cells.  相似文献   

3.
An alpha-subunit-secreting cell line derived from a mouse thyrotrope tumor.   总被引:4,自引:0,他引:4  
The anterior pituitary contains multiple distinct endocrine cell types that secrete individual hormones. To derive a pure cell culture population in which to study the regulation of the alpha-subunit of TSH free of other hormones and cell types, we have developed a clonal continuous cell line from the transplantable thyrotrope tumor MGH101A. This cell line expresses alpha-subunit mRNA, secretes alpha-subunit protein, and has maintained a stable phenotype for over 3 yr in culture. However, as is the case for the transplantable tumor from which they are derived, these cells do not express the beta-subunit of TSH or respond to TRH or thyroid hormone. We have used this cell line to investigate regulation of the alpha-subunit mRNA by the second messengers, cAMP and phorbol esters, and by glucocorticoids. Phorbol esters increase alpha-subunit mRNA levels significantly (3.5-fold), as does cAMP (1.8-fold). In contrast, glucocorticoids decrease mRNA levels from cAMP-induced or basal levels (2-fold). These cells should prove valuable for study of alpha-subunit gene expression in an isolated renewable clonal cell culture system.  相似文献   

4.
Summary The morphological, chromosomal, and biological characteristics of a cell line derived from a human chondrosarcoma have been described. At the time of this report, the cell line has undergone 102 passages and continues to exhibit an epithelioid appearance, a modal number of 69 chromosomes, and has retained malignant properties. This cell line is easily cultivated in vitro or in vivo and may prove useful in human cancer research.  相似文献   

5.
The aim of this study was to examine possible modulatory effects of some trophic molecules, i.e. nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF) and basic fibroblast growth factor (bFGF), on potassium (K(+))-, bradykinin (BK)- or capsaicin (CAPS)-evoked release of glutamate (GLU) from dorsal root ganglion (DRG) neurons in vitro. BK (0.5 and 1 microM) induced a dramatic and significant increase in glutamate release. Neither CAPS nor K(+) (60 mM) produced any significant increase of GLU release vs. basal levels during a 5-min stimulation. The BK-evoked release of GLU was almost completely blocked by HOE 140, a selective BK2-receptor antagonist at high doses. Basal release of GLU was significantly reduced in cultures grown in the presence of bFGF, whereas BDNF and NGF had no significant effect. Incubation with growth factors generally decreased the BK-stimulated GLU release, an effect most pronounced for bFGF, which completely blocked BK-stimulated release. The rise in intracellular [Ca(2+)] following stimulation with BK (100 nM-1 microM), potassium (60 mM) or ATP (10 microM) was also studied using a Ca(2+)-sensitive indicator, Fura-2, in cultures grown in basal medium with or without bFGF. None of the bFGF-treated cells exhibited strong Ca(2+) responses to BK or ATP stimulation, while 10-20% of the responding cells grown in basal medium exhibited strong responses. The K(+)-induced increase of [Ca(2+)] did not vary between the different groups.The present findings suggest that sensory neurotransmission involving glutamate may be modulated by growth factors and that regulation of intracellular Ca(2+) homeostasis may be a contributing factor.  相似文献   

6.
A Dray 《Life sciences》1992,51(23):1759-1765
Capsaicin produces pain by selectively activating polymodal nociceptive neurons. This involves a membrane depolarization and the opening of a unique, cation-selective, ion channel which can be blocked by ruthenium red. The capsaicin-induced activation is mediated by a specific membrane receptor which can be selectively and competitively antagonised by capsazepine. Repetitive administrations of capsaicin produces a desensitization and an inactivation of sensory neurons. Several mechanisms are involved. These include receptor inactivation, block of voltage activated calcium channels, intracellular accumulation of ions leading to osmotic changes and activation of proteolytic enzyme processes. Systemic and topical capsaicin produces a reversible antinociceptive and antiinflammatory action after an initial undesirable algesic effect. Capsaicin analogues, such as olvanil, have similar properties with minimal initial pungency. Systemic capsaicin produces antinociception by activating capsaicin receptors on afferent nerve terminals in the spinal cord. Spinal neurotransmission is subsequently blocked by a prolonged inactivation of sensory neurotransmitter release. Local or topical application of capsaicin blocks C-fibre conduction and inactivates neuropeptide release from peripheral nerve endings. These mechanisms account for localized antinociception and the reduction of neurogenic inflammation respectively.  相似文献   

7.
Further evidence for the establishment of the pig fallopian tube (PFT) cell line as a continuous cell line was shown by an increase in the maximum population density as the number of subcultures increased. The optimal pH and temperature-growth ranges appeared to be 7.4-7.8 and 37-41 degrees C respectively, and the population doubling time was 20-25 h under optimal growth conditions. With progressive subculture, the serum requirements dropped from 20 to 2%. A plating efficiency of 2 to 4% was found in all serial subcultures. Colonies were observed in agar suspension culture at the 146th subculture and thereafter. Chromosomal alterations were found in the 100th subculture and thereafter.  相似文献   

8.
A novel serous surface papillary carcinoma of the ovary (SSPC) cell line, HYKSSPC, was established successfully. Carcinoma cells were obtained from ascitic fluid of a 60-year-old Japanese woman. The population doubling time was 51.4 h. A phase contrast micrograph showed a pavement stone-like arrangement without contact inhibition. The chromosome number showed a wide distribution of aneuploidy, and the mode was in 46-47. An immunocytochemical study showed that CA125, BerER4 and cytokeratin were positive and that CEA, calretinin and thrombomodulin were negative. This cell line preserved some characters of the adenocarcinoma while growing in vitro. A chemosensitivity test revealed that HYKSSPC cells were sensitive to CDDP (cis-platinum), 5-fluorouracil, mitomycin C, paclitaxel and irinotecan. To our knowledge, HYKSSPC is the first established cell line derived from SSPC, and it may offer some useful information for investigating this disease.  相似文献   

9.
Nociceptive dorsal root ganglion (DRG) cells can be divided into three main populations, namely (1) small diameter non-peptide-expressing cells, (2) small-diameter peptide-expressing (calcitonin gene related peptide (CGRP), substance P) cells, and (3) medium-diameter peptide-expressing (CGRP) cells. The properties of these cell populations will be reviewed, with a special emphasis on the expression of the vanilloid (capsaicin) receptor VR1 and its regulation by growth factors. Cells in populations 1 and 2 express VR1, a nonselective channel that transduces certain nociceptive stimuli and that is crucial to the functioning of polymodal nociceptors. Cells in population 1 can be regulated by glial cell line derived neurotrophic factor (GDNF) and those in populations 2 and 3 by nerve growth factor (NGF). In vivo, DRG cells express a range of levels of VR1 expression and VR1 is downregulated after axotomy. However, treatment with NGF or GDNF can prevent this downregulation. In vitro, DRG cells also show a range of VR1 expression levels that is NGF and (or) GDNF dependent. Functional studies indicate that freshly dissociated cells also show differences in sensitivity to capsaicin. The significance of this is not known but may indicate a difference in the physiological role of cells in populations 1 and 2.  相似文献   

10.
11.
Bombesin is an amphibian tetradecapeptide whose mammalian homologue, gastrin-releasing peptide (GRP), is produced by many small-cell lung-cancer (SCLC) cells, and which can function in an autocrine growth-promoting manner in SCLC. Studies reported here show that [Tyr4]bombesin and its congeners increase inositol 1,4,5-trisphosphate within seconds in NCI-H345, a SCLC cell line that constitutively produces GRP. After 30 min in the presence of 0.01 M-Li+ and [Tyr4]bombesin, there is marked accumulation of inositol monophosphates and inositol tetrakisphosphate. Pretreatment with phorbol 12-myristate 13-acetate (PMA) for 20 min inhibited the ability of [Tyr4]bombesin to induce phosphatidylinositol (PtdIns) turnover and to increase intracellular free Ca2+ ([Ca2+]i). Pretreatment with PMA for 48 h attenuated the ability of subsequently added PMA to decrease the response to [Tyr4]bombesin. Pretreatment with pertussis toxin (PT; 1 microgram/ml for 18-24 h) decreased by less than 30% [Tyr4]bombesin-induced increases in [Ca2+]i and PtdIns metabolites. However, interpretation of this result is complicated by the inability of PT to ADP-ribosylate completely its substrates in intact NCI-H345 cells. In contrast, pretreatment with cholera toxin (1 microgram/ml for 18-24 h) lowered basal [Ca2+]i and basal inositol phosphate concentrations, attenuated the response of NCI-H345 to subsequently added [Tyr4]bombesin, and was not mimicked by treatments that increase cellular cyclic AMP. These data demonstrate the activation of phospholipase C in SCLC by bombesin congeners. In addition, the results suggest a regulatory role for protein kinase C, a cholera-toxin substrate, and perhaps a pertussis-toxin substrate in the response of SCLC to bombesin.  相似文献   

12.
13.
14.
The HK-1 cell line established from a human large cell lung carcinoma shows a high transformed phenotype and undifferentiated characteristics. This cell line grows as an adherent monolayer in fetal calf serum-supplemented medium, shows a high proliferation index, is able to grow in semi-solid agar and is tumorigenic in athymic nude rats. The cell line HK-2 derived from the HK-1 xenograft in athymic nude rats shows basically the same features found in the original HK-1 cell line, which include aneuploid nuclear DNA content, abnormal chromosomal number. rearranged marker chromosomes and abnormally localised nucleolar organizer regions. Cytokeratin and vimentin intermediary-sized filaments were found in both cell lines as well as in the original and induced tumour, while neither oncofetal antigens (alphafeto-protein, carcinoembryonic antigen, chorionic gonatropin and human placental lactogen) nor neural differentiation markers (neurofilament and neural specific enolase) were expressed. Analysis of sulphated glycosaminoglycans in the cell cultures and in the nude rat induced tumour showed high expression of chondroitin sulphate.  相似文献   

15.
The cell bodies of ascending noradrenergic neurons in the brain are located predominantly in the locus coeruleus. An in vitro model of locus coeruleus neurons could prove to be a useful tool in the investigation of noradrenergic neural networks and their associated pathophysiologies. The CATH.a cell line demonstrates some of the properties expected of locus coeruleus neurons, and the present study investigated the neurotransmitter uptake and release properties of the CATH.a cells. It was surprising that the CATH.a cells failed to accumulate [3H]noradrenaline ([3H]NA), suggesting the lack of a functional NA transporter. RT-PCR supported this finding by demonstrating the absence of NA transporter mRNA. Treatment of CATH.a cells with various differentiating agents failed to increase the [3H]NA uptake. Endogenous NA release was studied using HPLC detection, which revealed a lack of depolarisation-induced increases in endogenous NA release. A human NA transporter-transfected CATH.a cell line was generated (termed RUNT), and a study of the [3H]NA uptake revealed that the RUNT cells displayed significant uptake that could be blocked by cocaine (10 microM). Furthermore, the uptake capacity could be dramatically increased by differentiation of the cells with dibutyryl cyclic AMP (1 mM) for 24 h. Using dibutyryl cyclic AMP-differentiated RUNT cells, high K+ concentrations (50 mM) significantly increased [3H]NA release above basal levels.  相似文献   

16.
Summary Bovine tracheal submucosal gland cells have been isolated by enzymatic digestion and serially propagated in tissue culture for more than 12 mo. (40 passages). The cells exhibit an epithelioid appearance at confluence and contain alcian blue (pH 2.5)/periodic acid-Schiff-positive material within cytoplasmic granules. By electron microscopy numerous osmiophilic secretory granules are seen. Maximal growth is observed when the cells are grown on human placental collagen-coated culture vessels in medium supplemented with 20% fetal bovine serum. Scintillation spectrometry revealed that radiolabeled precursor (35SO4) was incorporated into high molecular weight molecules and released from cells. Isoproterenol (10−6 to 10−3 M) stimulated the release of35SO4. The maximal response to isoproterenol was completely inhibited by the β-adrenergic antagonist propranolol. It is concluded that the cultured cells retain features of tracheal gland cells and may serve as a useful model of synthesis and secretion of macromolecules by tracheal gland cells. This study was supported in part by NIH Program Project grant HL-24136, by a National Cystic Fibrosis Foundation Research Development Grant, and by a grant from Cystic Fibrosis Research, Inc. Dr. Finkbeiner is a recipient of NIH Clinical Investigator Award HL-01387.  相似文献   

17.
From a transplantable mouse teratoma it has been possible to derive an established keratinizing cell line (XB) which grows well in cultures containing lethally irradiated 3T3 fibroblasts at the correct density. Single cells of the keratinizing line grow into colonies each consisting of a stratified squamous epithelium. The keratinizing nature of the colonies has been demonstrated by specific staining with Rhodanile blue, and by light and electron microscopy of sections through the colonies. A function of fibroblasts appears to be a strict requirement for keratinization and an important though less strict requirement for cell growth. The fibroblast function can be carried out by medium harvested from 3T3 cultures.It is possible to detect keratinizing colonies in primary cultures of disaggregated teratoma cells combined with 3T3 cells. Such colonies appeared in cultures of a transplantable teratoma with an overall frequency of 6 × 10−6 of the cells plated. Nonkeratinizing colonies of cells with otherwise very similar appearance were about 10 fold more abundant. Since both the keratinizing and the related nonkeratinizing colonies can be identified in the living state, it is possible to isolate them from the primary cultures.  相似文献   

18.
An RNA-directed DNA polymerase was purified from a cell line derived from a radiation-induced lymphoma in NIH Swiss mice which produced non-infectious type C virus particles. The enzyme was isolated from a high speed particulate fraction which bands at a density of 1.16--1.19 g/ml in a sucrose gradient, and purified by successive chromatography on DEAE-cellulose, phosphocellulose and hydroxyapatite. The purified DNA polymerase has a molecular weight of 68 000, a pH optimum of 7.5, a KCl optimum of 50 mM, and a Mn2+ optimum of 0.25 mM. It prefers (dT)15 . (A)n to (dT)15 . (dA)n as the primer template and transcribes the poly(C) strand of (dG)15 .(C)n and (dG)15 . (OMeC)n. It transcribes heteropolymeric regions of avian myeloblastosis virus 70 S RNA, and is inhibited by antiserum to Rauscher murine leukemia virus DNA polymerase. Comparison of the properties of DNA polymerase purified from radiation-induced lymphoma cells with the DNA polymerase purified from non-defective murine type C RNA tumor viruses shows that the mouse lymphoma enzyme is both biochemically and immunologically related to murine leukemia virus DNA polymerases.  相似文献   

19.
A cell line, ROSE 199, derived from normal rat ovarian surface epithelium   总被引:4,自引:0,他引:4  
A cell line, ROSE 199, derived from rat ovarian surface epithelium (ROSE) formed papillary structures which resembled, histologically, serous papillary cystadenomas of borderline malignancy seen in the human ovary. Crowded cultures produced two layers of cells separated by a thick layer of collagen fibers. Such cultures shed viable cells into the growth medium, while no cells were shed by short-term ROSE cultures. The resemblance to ovarian tumors exhibited by ROSE 199 cells in culture, reinforces the hypothesis that the common epithelial tumors of the ovary are derived from the ovarian surface epithelium. ROSE 199 cells, while retaining their epithelial morphology and ultrastructural characteristics, express stromal activity such as abundant collagen production. Perhaps this ability to express epithelial and stromal behavior is a contributing factor to the ready neoplastic transformation of the ovarian surface epithelium.  相似文献   

20.
Characterization of a pluripotent stem cell line derived from a mouse embryo   总被引:15,自引:1,他引:15  
A pluripotent, karyotypically normal, male culture line ESC-BLC 1 of embryonal stem cells was established from delayed mouse blastocysts of strain 129/ter Sv. The cell line was isolated after cultivation of inner cell mass cells on X-irradiated feeder layer of mouse embryonal fibroblasts. The pluripotent status of the cell line was confirmed by in vivo and in vitro differentiation. For in vivo differentiation, cells were injected subcutaneously into syngeneic mice. The resulting tumors contained various tissues, derivatives of all three primary germ layers. In vitro cultivated pluripotent stem cells differentiated into endoderm-like, neuronal-like and tubular structures. Determination of alkaline phosphatase in cell line ESC-BLC 1 yielded a high specific activity; G-banding of metaphases revealed a normal, male karyotype.  相似文献   

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