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《畜牧兽医科技信息》2015,(12)
<正>胰蛋白酶抑制剂的抗营养作用普遍存在于饲料中,它不仅能与动物小肠液中的胰蛋白酶结合来降低胰蛋白酶的活性,还会引起动物体内蛋白质内源性消耗。消除饲料中胰蛋白酶抑制剂对动物体的影响是待解决的难题。本文针对胰蛋白酶在饲料中的抗营养作用作一综述。1胰蛋白酶抑制剂的分布及分类胰蛋白酶抑制剂,又被称作抗胰蛋白酶因子,分子式为C284H432N84O79S7。是一种具有生理活性功能的小分子量的蛋白 相似文献
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大豆中胰蛋白酶抑制因子的生化性质和抗营养作用 总被引：11，自引：0，他引：11
生大豆中含有许多抗营养因子影响其营养价值与利用效果,其中最主要的是胰蛋白酶抑制因子。本文总结了大豆中两大类胰蛋白酶抑制因子,即Kunitz类和Bowman-Birk类抑制因子的主要生化性质,以及含大豆胰蛋白酶抑制因子的日粮对不同种类动物的饲喂效果和生理反应。另外还介绍了胰腺分泌的蛋白酶与抑制因子的识别与反应机理,以及大豆胰蛋白酶抑制因子阻碍动物生长和引起胰腺增大的作用方式。最后讨论了在研究胰蛋白酶抑制因子的抗营养作用时,需要注意的几个问题。 相似文献
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1降低蛋白质利用率 胰蛋白酶抑制因子降低蛋白质消化、吸收、利用有以下两方的原因：(1)胰蛋白酶抑制因子可和小肠液中的胰蛋白酶和糜蛋白酶结合，生成无活性的复合物，消耗和降低胰蛋白酶和糜蛋白酶的活性，导致蛋白质的消化率和利用率下降；(2)引起动物体内蛋白质内源性消耗。胰蛋白酶抑制因子与胰蛋白酶结合形成的复合物随粪便排出体外，使肠道胰蛋白酶数量减少，引起胰腺机能亢进， 相似文献
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一、蛋白酶抑制因子。此因子存在于多种饲料中,如大豆、豌豆、菜豆等豆科籽实及黑小麦和黑麦。在小麦、水稻、燕麦和玉米的胚芽中也少量存在。其中以胰蛋白酶抑制因子的有害作用最大,它通过抑制胰蛋白酶的活性而降低蛋白质的消化率,抑制畜 相似文献
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豆粕是目前我国家禽配合饲料的主要蛋白质来源,约占家禽饲料的四分之一。豆粕质量的好坏直接关系到家禽饲料产品质量,影响到家禽生长和饲料转化率。大豆中含有抗营养因子,主要是胰蛋白酶抑制素,它抑制蛋白质的分解,降低蛋白质的消化或代谢物质的利用,因而使大豆的蛋白质营养价值降低。这些抗营养因子,多不耐热,在生产大豆油粕的过程中,大豆中大量抗营养因子被失活,其有害作用大为减少。许多资料指出,用标准工艺生产的大豆粕中,胰蛋白酶抑制素和尿素酶仍然具有一定活性。由于大豆中胰蛋白酶抑制素的活性与大豆中尿素酶活性成正相关,因此,常以豆粕尿素酶活性 相似文献
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挤压膨化对全脂大豆中的胰蛋白酶抑制因子和凝集素的影响 总被引：5，自引：0，他引：5
长期或短期喂给畜禽生大豆产生不利影响，归于大豆中的主要抗营养因子蛋白酶抑制因子和凝集素所致（Ｌｉｅｎｅｒ，１９８９）。蛋白酶抑制因子包括Ｋｕｎｉｔｚ胰蛋白酶抑制因子和ＢｏｗｍａｎＢｉｒｋ糜蛋白酶抑制因子，前者仅抑制胰蛋白酶的活性，后者既抑制胰蛋白酶又... 相似文献
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蛋白酶抑制因子 豆类饲料中的抗营养因子主要是蛋白酶抑制因子，它对动物的营养具有重要影响。蛋白酶抑制因子主要有KTI(胰蛋白酶抑制因子)和BBI(弓手抑制因子)两类，在大豆中含量尤其高。 相似文献
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蛋白质是动物养殖中非常重要的营养元素之一。更好的消化利用蛋白质,促进其它养分的充分利用,提高生长性能减少环境污染。因此,以饲料为底物最优化筛选而得到的蛋白酶会大大提高饲料中蛋白质的营养功效。本文将讨论饲料用偏碱性蛋白酶(EC 3.4.21.-)的特点和作用机理,主要包括以下方面:(1)其底物选择范围广,可水解不同来源的饲料蛋白质。(2)在不同的肠道pH值范围均具有活性:在小肠中性和碱性pH值范围活性最高,在胃中酸性pH值范围仍然具有较高活性。(3)在功能上与动物内源蛋白质消化酶具有互补性,可将动物内源蛋白消化酶不易降解的蛋白肽键有效降解。(4)不受植物原料中(如豆粕)胰蛋白酶抑制因子的影响。(5)可降解蛋白类抗营养因子(如胰蛋白酶抑制因子、植物凝聚素),从而降低其对动物生长性能的负面影响。(6)偏碱性蛋白酶与其它市售饲料酶具有协同作用。(7)可广泛应用到禽和猪饲料中,改善畜禽的生长性能。 相似文献
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绒山羊肥大细胞类胰蛋白酶的免疫组化及图像分析研究 总被引：1，自引：0，他引：1
[目的]探讨绒山羊肥大细胞中是否存在类胰蛋白酶及不同固定液对其常规染色和免疫组化染色结果的影响。[方法]采用兔抗羊肥大细胞类胰蛋白酶多克隆抗体间接免疫过氧化物酶技术检测由Carnoy液和中性福尔马林液(NBF)固定的绒山羊空肠、瓣胃和肺等组织肥大细胞中是否存在类胰蛋白酶。同时采用Image-ProPlus图像分析软件和人工计数法对结果进行分析,比较经常规染色和免疫组化染色后不同固定液固定组织中肥大细胞的形态及数量,进而判断Carnoy液和中性福尔马林液(NBF)对该检测技术的影响。[结果]兔抗羊多克隆抗体与绒山羊肥大细胞中的类胰蛋白酶具有良好的交叉反应,证实绒山羊肥大细胞胞浆颗粒中存在类胰蛋白酶。同时,与Carnoy液相比较,NBF液固定组织能较好地反映肥大细胞在组织中的数量和形态变化。[结论]绒山羊肥大细胞中存在类胰蛋白酶,且与Carnoy液相比较,NBF液是一种更为适合绒山羊肥大细胞常规染色和免疫组化染色的固定剂。 相似文献
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Decheng Wang Yufeng Liu Ruiping She Jingjing Xu Liqiang Liu Jinmao Xiong Yurong Yang Quan Sun Kaisong Peng 《Veterinary immunology and immunopathology》2009,131(3-4):229-237
Recent studies here have demonstrated that increased mast cell populations and tryptase activity contribute to lesion formation in regions of immune organs in special-pathogen-free chickens after infection with very virulent infectious bursal disease virus (vvIBDV). Mast cells and their mediators have been implicated in acute inflammatory injury after vvIBDV infection, but their precise role in this process remains elusive. In this study, the role of mast cells in the vvIBDV infection process was examined using ketotifen, a mast cell membrane stabilizer. On days 1, 2, and 3 postinfection, the bursa of Fabricius (BFs) were collected to quantify mast cells, tryptase and histamine contents by cytochemistry, immunohistochemistry and fluorospectrophotometry analyses, respectively. The results showed that the mast cell populations, tryptase expression, and histamine released increased significantly in the BFs (p < 0.01) of infected birds compared to controls, and acute inflammatory responses were observed in the former. In contrast, in infected chickens pretreated with ketotifen, mast cells, tryptase, and histamine were markedly decreased (p < 0.01) and probably as a result, the BFs remitted significantly. The overall results suggest that mast cells are positively involved in BF injury induced by vvIBDV infection. Inhibition of mast cell degranulation and concurrent mediator release may represent a novel strategy to modulate this process. This study, thus, advances the understanding of the acute inflammatory injury mechanisms triggered by vvIBDV infection and the contribution of mast cell activity in this process. 相似文献
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The aim of this study was to establish the immunocytochemical expression of S‐100 protein in mast cells, localized in the wall of dog's paranal sinus. Control serial sections were used for immunocytochemical detection of tryptase‐positive mast cells. It was observed that S‐100‐positive cells have the same morphology and localization as the tryptase‐positive mast cells, which indicated that S‐100‐positive cells are most probably mast cells with abilities as dendritic cells. In conclusion, for the first time, the current study gave evidence that mast cells in this organ possess one more function, such as dendritic cells. 相似文献
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Immunohistochemical and histochemical stains are useful adjunct techniques in the diagnosis of canine cutaneous round cell tumors, which can appear histologically similar. We applied a panel of monoclonal antibodies (recognizing tryptase, chymase, serotonin for mast cells; CD1a, CD18, MHC class II for histiocytes; CD3 for T lymphocytes; CD79a for B lymphocytes and plasma cells) and one histochemical stain (naphthol AS-D chloroacetate for chymase activity) to formalin-fixed, paraffin-embedded sections of canine cutaneous mast cell tumors, histiocytomas, lymphosarcomas, plasmacytomas, and unidentified round cell tumors. Of 21 tumors with a histologic diagnosis of mast cell tumor, 7/7 (100%) grade I, 6/7 (85.7%) grade II, and 3/7 (42.9%) grade III tumors were diagnosed as mast cell tumors based on positive staining for tryptase antigen and chymase activity. Mast cells were positive for both tryptase antigen and chymase activity, indicating equal efficacy of tryptase immunohistochemistry and chymase histochemistry. Chymase was detected immunohistochemically in both tumor and nontumor cells, while serotonin was not detected in most mast cell tumors, and thus, neither was useful in the diagnosis of mast cell tumors. Immunohistochemistry to detect CD18 and MHC class II was equally effective in staining histiocytomas, although lymphosarcoma must be ruled out through the use of CD3 and CD79a immunohistochemistry. Immunohistochemistry using three different monoclonal antibodies to human CD1a showed no cross-reactivity in canine histiocytomas and was not useful. A final diagnosis was obtained for 4/5 (80%) of the unidentified tumors, indicating the usefulness of multiple stains in poorly differentiated round cell tumors. 相似文献
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Q fever is an infectious disease due to Coxiella burnetii. Following a primary-infection, C. burnetii may persist in some patients, leading to endocarditis and vascular infections. Mast cells (MCs), known for their role in allergic diseases, innate immunity and cardiac function, are produced by bone marrow, circulate as progenitors in the bloodstream and reach tissues for their maturation and activation. The latter may be estimated by measuring serum tryptase levels. We wondered if MC progenitors and tryptase were affected in Q fever. We showed a decrease in MC progenitor count in Q fever patients whereas serum tryptase levels were increased. Taken together, our results show alterations of MC numbers and activity in Q fever patients, suggesting that MC are involved in Q fever pathophysiology. 相似文献
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Mast cell mediated inflammatory response in chickens after infection with very virulent infectious bursal disease virus 总被引：1，自引：1，他引：0
Wang D Xiong J She R Liu L Zhang Y Luo D Li W Hu Y Wang Y Zhang Q Sun Q 《Veterinary immunology and immunopathology》2008,124(1-2):19-28
The potential role of the mast cells in the invasion of very virulent infectious bursal disease virus (vvIBDV) is unknown. We evaluated mast cell activity and tryptase production after vvIBDV infection in special pathogen-free (SPF) chickens using cytochemistry and immunohistochemistry analyses. The results were as follows: (1) severe histologic lesions were observed in the thymus, spleen, cloacal bursa, liver, kidney and other tissues. vvIBDV viral antigens were detected and presented extensively in the parenchymatous organs, in particular, the cloacal bursa, liver, kidney, thymus, spleen and pancreas. (2) In the vvIBDV-infected group, the mast cell population increased markedly in the liver, kidney, thymus, glandular stomach, spleen and cloacal bursa on days 1, 2 and 3 after vvIBDV infection (p<0.05). However, very few mast cells were observed in those same tissues in the controls, especially in the bursa of Fabricius. (3) Tryptase, a marker for activated mast cells, has a positive correlation with mast cell distribution. The mast cells identified in the tissues were likely to be activated since they were associated with cell degranulation and the presence of tryptase. Furthermore, the co-localization of mast cells, and presence of vvIBDV antigens suggests that the mast cells were activated by vvIBDV infection. Our results also suggest that tryptase may contribute to the inflammation of acute IBD induced by vvIBDV infection. Our research contributes to the further understanding of inflammatory response mechanisms and the contribution of mast cell activity to this process. 相似文献
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Abstract We investigated the influence of vitamin E on mediator activity and release in a canine mastocytoma cell line (C2) as a model for canine atopic dermatitis. Cells were incubated without and with vitamin E (100 µ m ) for 24 h. The histamine and prostaglandin D2 (PGD2 ) release as well as the chymase and tryptase activity were measured. To stimulate the PGD2 and histamine release, cells were incubated with the wasp venom peptide mastoparan (50 µ m ) for 30 or 45 min. Nonstimulated as well as mastoparan-stimulated histamine and PGD2 release was reduced significantly in vitamin E-treated cells. The activity of chymase tended to decrease, but the tryptase activity of C2 cells was not influenced by vitamin E. These results indicate that vitamin E decreased the production and release of inflammatory mediators in C2 cells, suggesting that vitamin E might have a possible beneficial effect in inflammatory diseases. 相似文献
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Rüfenacht S Marti E von Tscharner C Doherr MG Forster U Welle M Roosje PJ 《Veterinary dermatology》2005,16(2):94-101
The pathogenesis of equine urticaria is not well understood. In man, urticaria has been associated with immunological and nonimmunological mechanisms leading to the release of various mediators by mast cells. Skin biopsies of 32 horses with a history of urticaria were stained with toluidine blue, a double-labelling method for chymase and tryptase, and immunohistochemistry for immunoglobulin (Ig)E. These horses were compared with horses with pemphigus foliaceus, insect bite hypersensitivity and control horses with healthy skin. Neither formalin fixation time nor biopsy site influenced the staining methods. No chymase-positive cells were found. In all groups of horses, cells staining with toluidine blue and for tryptase and IgE were found in the epidermis and hair follicle papilla and significantly more positively staining cells were observed in the subepidermal dermis compared with the deep dermis. Horses with urticaria had significantly more IgE-bearing cells in the subepidermal dermis than control horses. However, horses with urticaria had significantly fewer toluidine-blue-stained mast cells in both subepidermal and deep dermis compared with the insect bite hypersensitivity and pemphigus foliaceus groups. This study suggests that IgE-mediated reactions play a role in the pathogenesis of urticaria. 相似文献