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1.
Ultrastructural changes in the cells of the proper gastric glands and their stroma are biphasic in the hemorrhagic shock. First phase: "paralysis" of the capillary vessels with an oedema of their stroma, an intracellular oedema with hydropic degeneration of the parietal cells and a degranulation of the argentaffin and argentaffin-like cells. Second phase: ischemia of the gastric mucosa with ultrastructural features of: a) the increased secretion of the parietal cells, b) the degranulation of the chief gastric cells, c) the increased secretion processes in the mucous neck cells. These findings suggest that at last 2 factors coincide in the pathogenesis of so-called stress gastric ulcerations: biphasic disturbances of blood circulation initially damage the gastric mucosa and are followed the digestive hyperactivity of the gastric juice finally resulting stress ulceration.  相似文献   

2.
Effect of disodium cromoglycate on cutaneous basophil anaphylaxis   总被引:1,自引:0,他引:1  
Cutaneous basophil anaphylaxis (CBA) was elicited by intradermal rechallenge of cutaneous basophil hypersensitivity (CBH) sites in guinea pigs sensitized 7 days previously with keyhole limpet hemocyanin (KLH). The antiallergy agent disodium cromoglycate (DSCG), administered i.v. immediately before rechallenge, inhibited the increased vasopermeability (measured by tissue dye uptake) and basophil degranulation (measured by light microscopic counts of intact basophils) characteristic of the CBA reaction. The antihistamine mepyramine, administered orally, inhibited vasopermeability but not basophil degranulation. The component contributed by DSCG inhibition of mast cell degranulation to the overall inhibition of the reaction was found to be minimal, since intact mast cells were found to be depleted at CBH sites and totally absent at CBA sites from animals treated with DSCG. Electron microscopic examination of basophils at CBA sites from DSCG-treated animals revealed the presence of ruffled perigranular membranes and enlarged perigranular spaces, but both the formation of degranulation sacs and the subsequent fusion of granule sac membranes with the plasma membrane were inhibited. DSCG also inhibited the vasopermeability and basophil degranulation of the CBA reaction elicited by KLH at day 14 and by C5a at day 7. When a basophil-enriched leucocyte preparation from KLH-sensitized guinea pigs was studied in vitro, DSCG inhibited both antigen-induced and C5a-induced basophil degranulation at 10(-5) and 10(-4) M. DSCG failed to inhibit the vasopermeability and the mast cell degranulation produced by either intradermal C5a or intradermal compound 48/80. These results indicate that anaphylactic degranulation of basophils, but not mast cells, is inhibited by DSCG in the guinea pig. This inhibition appears to take place independent of stimulus at an early stage of granule membrane fusion.  相似文献   

3.
Response of mast cells to stress has a systemic character, being observed in organs both determining development of stress reaction (thymus, bone marrow, adrenals, stomach, duodenum) and not participating in this process (skin, liver). The reaction of mastocytes is manifested as a total degranulation. Mast cell secretion is regulatory by its nature, and biologically active compound are released directly on the target cells. Along with degranulation, which is observed in organs participating in stress reaction formation, migration of mast cells takes place, resulting in their redistribution.  相似文献   

4.
Protective vasodilation in response to tissue injury and acid back diffusion is associated with release of bradykinin in the rat stomach. We hypothesized that bradykinin might be involved in mechanisms behind such vasodilation via influence on mast cells and sensory neurons. Acid back diffusion after mucosal barrier disruption with hypertonic saline evoked degranulation of mast cells in the rat stomach wall. Acid back diffusion was also associated with increased luminal release of histamine and gastric blood flow in normal rats, but not in mast cell-deficient rats. Bradykinin (BK(2)) receptor blockade inhibited degranulation of submucosal mast cells in the stomach and attenuated gastric vasodilation both in response to acid back diffusion and after stimulation of sensory neurons with capsaicin. Gastric vasodilation caused by mucosal injury with hypertonic saline alone was associated with degranulation of mucosal mast cells. These events were unaffected by inhibition of prostaglandin synthesis, whereas bradykinin (BK(2)) receptor blockade was associated with abolished vasodilation and inhibition of mucosal mast cell degranulation. We conclude that bradykinin is involved in gastric vasodilation caused by hypertonic injury alone via influence on mast cells, and by acid back diffusion via influence on both sensory neurons and mast cells.  相似文献   

5.
Membranous organelles, acid glycoconjugates and lipids were characterized in the digestive tract mucosa of Hemisorubim platyrhynchos by cytochemistry techniques. Two types of mucous‐secreting cells were observed in the digestive tract epithelium: goblet cells in the oesophagus and intestine and epithelial cells in the stomach. These cells had a Golgi apparatus more developed than the other cell types. The cytochemical analysis revealed that secretory granules are reactive to acid glycoconjugates, varying in reaction intensity according to the region of the digestive tract. Acid glycoconjugate reactions were also observed in oesophageal epithelial cell microridges and in enterocyte microvilli. In the digestive tract, acid glycoconjugates act to protect the epithelial surface, increasing mucous viscosity, which facilitates the passage of food, prevents the binding of parasites and facilitates their removal. Through lipid staining, a coated membrane was observed around each secretory granule of the oesophageal and intestinal goblet cells, while gastric epithelial cells granules were fully reactive. Oxynticopeptic cells of the gastric glands showed lipid droplets in the cytoplasm and also in the mitochondrial matrix, which act as an energy reserve for these cells that have a high energy demand. Enterocytes showed a well‐developed smooth endoplasmic reticulum, especially in the apical region of the cell, being related to absorption and resynthesis of lipids.  相似文献   

6.
The head kidney and spleen are major sites of haemopoiesis in fish; a secondary center is found in loose connective tissue of the intestine. In this study we determined the nature of gut-associated haemopoietic tissue in the goldfish, Carassius auratus, using light and electron microscopy. This tissue is a loose stroma of reticular cells and fibers vascularized by capillaries, venules, and arterioles. The cellular population includes lymphoblasts, small and medium-sized lymphocytes, plasmocytes, macrophages, and various granulocytes. The most abundant granulocyte is the mast cell, whose large granules stain with Alcian blue and toluidine blue. Heterophils are found in the intestinal connective tissue as well as two other granulocytes: one with ovoid granules having dense parallel lamellae and another with granules containing crystalline inclusions. Immature forms of both granulocytes were also noted. Macrophages containing phagocytosed debris were often located close to the epithelium; they were observed forming clusters with lymphocytes. The epithelium contained a number of migrating leucocytes including lymphocytes and lymphoblasts, macrophages, and heterophils. Although many granulocytes were found in the connective tissue, granulopoiesis does not seem to be a major function. Gut-associated haemopoietic tissue in goldfish resembles diffuse lymphoid tissue and may be involved in intestinal immune responses.  相似文献   

7.
食管癌胃癌间质中肥大细胞淋巴细胞光镜与电镜研究   总被引:1,自引:0,他引:1  
对35例食管癌与30例胃癌间质中的肥大细胞与淋巴细胞进行光镜与电镜观察。结果发现,两种癌间质中的肥大细胞数量在恶性程度低组均比恶性程度高组与对照组显著增加。在各组食管癌或胃癌中,有淋巴细胞高度浸润并形成淋巴小结者,肥大细胞也增多。用Alcian蓝—藏红染色,对照组Alcian蓝阳性和藏红阳性的肥大细胞都可以见到;而在食管癌胃癌间质中,大部分肥大细胞均呈Alcian蓝阳性。电镜观察,对照组肥大细胞颗粒多具有涡卷状结构,而癌组者则显示多样化形态。一些肥大细胞和淋巴细胞与癌细胞接触,肥大细胞可见活跃脱颗粒现象。结果提示,在抗肿瘤生长的防御机制中,肥大细胞与淋巴细胞有协同作用。  相似文献   

8.
鳜鱼消化道黏液细胞和6种酶的组织化学定位   总被引:1,自引:0,他引:1  
采用阿利新蓝-过碘酸雪夫氏(AB-PAS)染色和酶组织化学方法对鳜鱼消化道各部位黏液细胞和6种酶的分布与定位进行了研究。结果显示,黏液细胞可为分为4种类型,食道黏液细胞多数为Ⅲ型和Ⅳ型,未见Ⅰ型和Ⅱ型;胃贲门和胃幽门黏膜上皮仅有Ⅰ型黏液细胞;胃体黏膜上皮则以Ⅲ型细胞为主;幽门盲囊中主要为Ⅱ型细胞;前肠和中肠中Ⅳ型黏液细胞最多,Ⅰ型最少;后肠黏液细胞则以Ⅳ型和Ⅱ型为主。酸性磷酸酶(ACP)主要分布于幽门盲囊和前肠的黏膜上皮;碱性磷酸酶(ALP)主要分布于食道、幽门盲囊和整个肠道黏膜上皮;非特异性酯酶(NSE)主要分布于胃幽门、中肠和后肠黏膜上皮;过氧化物酶(POX)在胃幽门黏膜上皮中活性较高;琥珀酸脱氢酶(SDH)主要分布于胃腺中;腺苷三磷酸酶(ATPase)在消化道各部位均有较多分布。鳜鱼消化道黏液细胞和酶的分布型与其它动物有相似之处,也有其一定的特异性,与消化道不同部位的消化吸收机能相适应。  相似文献   

9.
H Heine  G Schaeg 《Acta anatomica》1977,98(3):275-280
The morphology of the globule leukocyte (GL) has been investigated by light and electron microscopy in normal (decidua of mouse placenta) and pathologically altered tissues (tumors of epidermis and mucous membrane in men). The results make it probable that the GL my originate from mast cells as well as from eosinophil granulocytes. The high content of basic proteins within the globules of GL has been interpreted as a nutritive function by this cell type to the surrounding tissue.  相似文献   

10.
Damselfish neurofibromatosis (DNF) is a neoplastic disease affecting bicolor damselfish (Stegastes partitus Poey) on Florida reefs. Previous studies have demonstrated high densities of eosinophilic granule containing cells (EGC), the proposed equivalent of mast cells in fishes, in neurofibromas and malignant peripheral nerve sheath tumors (mpnst) in DNF. These lesions are similar to those in the disease neurofibromatosis type 1 (NF1) in humans, which contain large numbers of mast cells. In the present study, experiments were conducted to measure the response of EGC in these tumors as well as in the submucosa of the digestive tract to the mast cell degranulating agent compound 48/80. Degranulation of these cells was visible by light microscopy and characterized by conspicuous swelling of granules and often by the presence of free granules adjacent to the EGC. Degranulation occurred by release of intact granules (diacytosis), as reported in other fishes, rather than by fusion of granules with the cell membrane (exocytosis) as reported in mast cells in mammals. Baseline levels of EGC exhibiting degranulation ranged from 20-26% in the submucosa to 30% in tumors. Within 1-2h of exposure to compound 48/80, significant increases in average levels of degranulation were observed, to 67% in the gut and 72% in tumors. Degranulation was significantly more extensive in the tumors than in the gut. The outermost edges of the tumors contained significantly higher densities of EGC but these cells exhibited lower rates of degranulation than those in the inner regions of tumors. These observations support the hypothesis that the EGC present in neurofibromas and mpnst in DNF are equivalent to the mast cell component in neurofibromas in NF1.  相似文献   

11.
Ovaries from hamsters on each day of the oestrous cycle at 09.00 h were observed for the number of mast cells, the pattern of mast cell degranulation, histamine concentration and blood flow. On day 4 (pro-oestrus), ovaries were also observed at 9.00, 15.00 and 21.00 h. Mast cell degranulation was evaluated by 3 criteria: (1) no degranulation = less than 5 granules dispersed from the cell; (2) moderate degranulation = 5 or more granules dispersed but less than 15, and (3) extensive degranulation = 15 or more granules released. Blood flow was determined using radio-active microspheres in anaesthetized animals. Mast cells were observed in fat pad (beyond 2 mm of the bursal mesothelium), bursa (within 2 mm of the bursal mesothelium), hilum and near ovarian blood vessels (these 4 regions are collectively called the ovarian complex). The distribution of ovarian mast cells was not uniform. Most mast cells were near ovarian blood vessels (42.2%) and in the fat pad (37.2%). A moderate number of cells were in the bursal wall (20%) and only a few cells were observed in the hilum (0.64%). Mast cell number remained unchanged on days 1-4 of the cycle in each ovarian compartment. However, summation of the number of mast cells in the entire ovarian complex revealed a significant decline in number at 15.00 h on pro-oestrus. Alterations in mast cell degranulation were primarily restricted to 2 periods of the cycle (pro-oestrus and di-oestrus). An increase in moderate but not extensive degranulation was observed in only the fat pad and bursa on day 2 when compared with day 1 values. In most ovarian compartments on pro-oestrus, degranulation was higher than on any other day of the cycle. At 15.00 h on pro-oestrus, extensive degranulation in bursa, fat pad and blood vessel regions (but not hilum) coincided with an increase in ovarian histamine and decline in number of mast cells; ovarian blood flow also increased at the time but remained unchanged the remainder of the cycle.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

12.
Carnosine (beta-alanyl-histidine) is a naturally occurring dipeptide that has been characterized as a putative hydrophilic antioxidant. The protective function of carnosine has been demonstrated in neuronal cells under ischemic injury. The purpose of this study was to investigate the effects of carnosine on oxygen-glucose deprivation (OGD)-induced degranulation and histamine release from mast cells. Cultured mast cells were exposed to OGD for 4 h, and then the degranulation was observed immediately by microscopy. Histamine release was analyzed by high-performance liquid chromatography (HPLC). OGD caused degranulation of mast cells, and increased histamine and lactate dehydrogenase (LDH) release. Carnosine (at a concentration of 5 mM) alone did not produce any appreciable effect on degranulation, histamine, and LDH release from mast cells under normal condition, but significantly inhibited the degranulation, histamine, and LDH release of mast cells induced by OGD. These results indicate that carnosine can protect mast cells from degranulation and histamine release and it may be an endogenous mast cell stabilizer in the pathological processes induced by ischemia.  相似文献   

13.
Pretreatment of mouse mast cells with 10(-7) to 10(-6) M dexamethasone (DM) during overnight sensitization with mouse IgE antibody resulted in inhibition of antigen-induced histamine release and degranulation. The inhibition of both degranulation and histamine release increased linearly with the duration of the treatment; maximal inhibition was obtained after approximately 16 hr with DM. The addition of DM to sensitized mast cells immediately before antigen challenge did not affect the antigen-induced histamine release. DM interacted directly with mast cells by binding to DM-specific cytoplasmic receptors. The treatment of mast cells with DM did not affect the binding of IgE to mast cells or intracellular cAMP levels. Bridging of cell-bound IgE anti-DNP antibody on mouse mast cells either by multivalent DNP-HSA or by anti-IgE induced phospholipid methylation at the plasma membrane and Ca++ influx into the cells. Pretreatment of mast cells with DM inhibited the antigen-induced phospholipid methylation and Ca++ uptake but failed to affect histamine release by Ca++ ionophore A23187. The results suggest that DM treatment inhibits histamine release by the inhibition of the early stage of biochemical processes leading to opening Ca++ channels but does not affect the process distal to Ca++ influx or the binding of IgE molecules to IgE receptors.  相似文献   

14.
Suzuki K  Verma IM 《Cell》2008,134(3):485-495
Mast cells are known to play a pivotal role in allergic diseases. Cross-linking of the high-affinity receptor for IgE (FcepsilonRI) leads to degranulation and allergic inflammation; however, the regulatory mechanisms of IgE-dependent exocytosis remain unknown. We show here that IkappaB kinase (IKK) 2 in mast cells plays critical roles in IgE-mediated anaphylaxis in vivo, and IgE-mediated degranulation in vitro, in an NF-kB-independent manner. Upon FcvarepsilonRI stimulation, IKK2 phosphorylates SNAP-23, the target membrane soluble N-ethylmaleimide-sensitive fusion factor attachment protein receptor (SNARE), and ectopic expression of a phospho-mimetic mutant of SNAP-23 partially rescued the impaired IgE-mediated degranulation in IKK2-deficient mast cells. These results suggest that IKK2 phosphorylation of SNAP-23 leads to degranulation and anaphylactic reactions. While this reaction is NF-kB-independent, we additionally show that IKK2 also regulates late-phase allergic reactions promoted by the release of proinflammatory cytokines in an NF-kB-dependent manner. The findings suggest that IKK2 is a central player in allergic reactions.  相似文献   

15.
长薄鳅外周血细胞可分为红细胞、中性粒细胞、单核细胞、淋巴细胞和血栓细胞.在数量上,中性粒细胞、单核细胞、淋巴细胞和血栓细胞占白细胞总数的百分比分别是17.06%、5.83%、28.16%和48.94%.细胞化学染色显示所有白细胞均含有糖原物质,所有红细胞均不含酸性磷酸酶,中性粒细胞、单核细胞、淋巴细胞和血栓细胞均含有酸性磷酸酶.非特异件酯酶染色显示单核细胞呈阳性反应,中性粒细胞、淋巴细胞和血栓细胞均为部分呈阳性反应.所有细胞的碱性磷酸酶、过氧化物酶、苏丹黑显色反应均呈阴性.  相似文献   

16.
应用光学显微镜观察龟足(Capitulum mitella)消化系统的形态和组织结构。龟足的消化系统包括消化腺和消化道。消化腺一对,呈长囊状,含有分泌细胞(B细胞)、吸收细胞(R细胞)、储存细胞(F细胞)和胚细胞(E细胞)4种类型细胞。消化道呈U型,由口、食道、胃、肠、直肠和肛门组成,各部分的结构由内到外可分为黏膜层、黏膜下层、肌层和外膜4层。口器为咀嚼型,包括一片上唇、一对触须、一对大颚以及两对小颚。食道细短,具几丁质层但无基膜,管壁向腔内突起形成明显的纵褶突;食道前段的环肌特别发达,同时独有放射肌。胃略呈球袋状,肠较长;胃和肠的组织结构相似,没有几丁质层,上皮细胞都有发达的微绒毛。直肠细长,外膜分布有16组纵肌;直肠前段的组织结构与胃、肠相似,而直肠后段有几丁质层覆盖,黏膜层、黏膜下层、肌层和外膜渐退化,16组纵肌渐发达。肛门16组更加发达的纵肌挤入上皮细胞下方,在外膜外另出现一层明显的环肌。龟足消化道各部分的组织结构差异明显,反映了它们功能的差异。  相似文献   

17.
An adenosine triphosphatase (ATP) activated by Ca2+ or Mg2+ is shown morphologically on the outer surface of non-secreting and secreting rat peritoneal mast cells. ATPase having the same properties is also seen on the external surface of the other peritoneal cells, i.e. macrophages, mononuclear cells and lymphocytes. When histamine release from the mast cells was induced by exposing them to antigen (anaphylactic reaction) or compound 48/80, ATPase activated by Ca2+ or Mg2+ could in addition be demonstrated in the granule membranes. Granule membrane ATPase is also shown in non-secreting mast cells after freezing and thawing. ATPase on the outer surface of the plasma membrane is seen in the secreting mast cells as in the non-secreting cells except in the areas where the plasma membrane fuses with the granule membrane. The role of ATPase in granule secretion process has been discussed.  相似文献   

18.
Degranulation of IgE-sensitized rat mast cells by antigen was studied quantitatively in vitro and in vivo by electron microscopy. The inhibition of this degranulation by an anti-allergic drug, N-(3,4-dimethoxycinnamoyl)anthranilic acid (Tranilast), was also examined both in vitro and in vivo. In the in vitro study using peritoneal mast cells, alteration of the granules, cavity formation by fusion of the perigranular membrane and granule discharge due to fusion of the cavity membrane with the cell membrane were observed and were accompanied by histamine release. Scanning electron microscopy disclosed the extrusion of smooth, round bodies from pores formed on the cell surface. In the in vivo study of passive cutaneous anaphylaxis (PCA), the characteristic features of mast cell degranulation were obvious 5 min after the injection of antigen; leakage of dye increased progressively from 5 to 30 min but was not found at 6 h. From quantitative analysis of the substructure of mast cells, it was demonstrated that degranulation of IgE-sensitized mast cell induced by antigen was achieved by sequential exocytosis both in vitro and in vivo. Tranilast inhibited these changes to a remarkable extent and it was concluded that the inhibition of mast cell degranulation by this drug might play an important role in anti-allergic treatment.  相似文献   

19.
The correlations among the potentiating activity of various PS analogs on concanavalin A (Con A)-induced rat mast cell degranulation, the hemolytic activity and the incorporation into the mast cell membrane were studied. The following results were obtained. Lysophosphatidylserine (LysoPS) caused rat mast cell activation (degranulation) in the presence of Con A. The order of the activity was as follows: 1-stearoyl lysoPS = 1-palmitoyl lysoPS greater than 1-myristoyl lysoPS greater than 1-lauroyl lysoPS. The relative hemolytic activity of these compounds was similar to that observed in the mast cell activation. Dilauroyl PS, which shows similar hemolytic activity to 1-myristoyl lysoPS, did not activate mast cells appreciably. The relative activity of these phospholipids in the binding to mast cells was 1-stearoyl lysoPS greater than dilauroyl PS greater than 1-lauroyl lysoPS. Hemolytic activity, as well as activity on mast cells, of lysoPS analogs was well correlated to mast cell membrane incorporation, whereas such a correlation was not found with PS analogs. Dilauroyl PS could be accumulated in the mast cell membrane and showed hemolytic activity, but did not activate histamine secretion.  相似文献   

20.
Regional popliteal lymph nodes in intact, control and experimental (I, II, III groups, respectively) have been studied by means of the morphometric method in male C57Bl/6 line mice at the pick of the reaction produced by injection of spleen cells and mesenteric lymph nodes obtained from syngenic females and repeatedly immunized to H-Y antigen (10 animals in each group). Injection of the cell suspensions from the immunized and intact females of the C57Bl/6 mice result nearly in two-fold increasing mass of the regional popliteal node at the expense of enlarged size of all its zones. Changes in cytoarchitectonics of the node structural components result from redistribution of certain cellular elements. The essential changes in the cell composition of the lymph nodes in the II and III male groups are accompanied with an increasing part of the stromal reticular cells. Simultaneously, content of small lymphocytes decreases significantly. In the III group of mice there is a sharp increase in the content of young forms of the lymphoid line cells in all structural components of the node, as well as in eosinophilic granulocytes in medullary cords. In the dark cortical zone of the nodes (III group) there occur tissue basophils (mast cells), that, together with increasing number of acidophilic granulocytes and appearance of neutrophilic cells, demonstrates that there is an inflammatory reaction in the organ studied as a response to the lymphocytic suspension injected. In the experimental group of the animals a complete disappearance of plasma cells is noted in the node cortex, but some increase of their part takes place in the medullary cords.  相似文献   

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