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1.
本实验发现苦刺总生物碱中的新成分13a-羟苦参碱(13a-hydroxymatrjne)具有对抗水浸应激性小鼠溃疡和吲哚美辛加乙醇所致小鼠溃疡,但对盐酸性大鼠溃疡和结扎门性大鼠溃疡形成无对抗作用。又发现去槐果碱后的苦刺总生物碱具有比13a-羟苦参碱更强的抗溃疡活性。  相似文献   

2.
尖顶羊肚菌菌丝体水提液对实验型胃溃疡的作用   总被引:1,自引:0,他引:1  
研究尖顶羊肚菌菌丝体水提液对4种实验型胃溃疡模型的治疗作用。以大鼠幽门结扎致胃溃疡为模型,测定各组胃粘膜损伤指数、胃液分泌量和胃酸浓度;以大鼠乙酸烧灼、小鼠乙醇致胃粘膜损伤和小鼠水浸应激胃溃疡为模型,分别测定溃疡面积。结果表明尖顶羊肚菌菌丝体水提液可以不同程度抑制胃酸的分泌,减少胃液量,减少溃疡面积,促进溃疡面积的愈合,因此尖顶羊肚菌菌丝体水提液具有抗实验型胃溃疡的作用。  相似文献   

3.
川木香对实验性胃溃疡形成的抑制作用研究   总被引:1,自引:0,他引:1  
目的:研究川木香对实验性胃溃疡形成的抑制作用.方法:采用利血平型小鼠胃溃疡模型、醋酸型大鼠胃溃疡模型,以雷尼替丁为对照药物,观察动物溃疡指数和溃疡抑制率.结果:川木香单体提取物(去氢木香内酯)、醋酸乙酯提取物、乙醇提取物,抑制利血平型溃疡存在统计学差异(与模型对照组比较,P<0.01);醋酸乙酯提取物,抑制醋酸型溃疡存在统计学差异(与模型对照组比较,P<0.05),其中高剂量组作用存在统计学差异(与模型对照组比较,P<0.01).结论:川木香具有抑制实验性胃溃疡的形成作用,醋酸乙酯提取物可以作为川木香抑制胃溃疡形成的有效部位.  相似文献   

4.
目的:研究槐角黄酮栓的抗炎、止血、抗溃疡作用。方法:从中药槐角中提取总黄酮,与脂肪酸甘油酯混合后用热融法制成栓剂。采用小鼠耳廓肿胀法、滤纸肉芽肿法、腹腔毛细血管通透性试验和角叉菜胶致大鼠足跖肿胀法观察槐角黄酮栓的抗炎作用;通过玻璃毛细管法和断尾法测定小鼠出、凝血时间,评价槐角黄酮栓的止血效果。复制大鼠直肠损伤模型,直肠给药治疗,观察伤口愈合情况并HE染色,评价槐角黄酮栓的促愈合作用。结果:槐角黄酮栓具有明显的抗炎、抗溃疡作用,并能缩短小鼠出、凝血时间,提高直肠创面愈合率。结论:槐角黄酮栓制备工艺简单,具有较好的抗炎、止血、抗溃疡作用。  相似文献   

5.
目的:探讨左旋紫草素的抗炎药理作用.方法:采用二甲苯涂抹小鼠耳面,致使毛细血管渗出导致耳肿胀和醋酸所致小鼠腹腔毛细血管通透性增高的炎症模型,观察左旋紫草素对急性炎症的对抗作用;采用大鼠腋窝皮下置无菌棉球的炎症模型,观察左旋紫草素对亚急性炎症的对抗作用.结果:与生理盐水组比较,左旋紫草素低、中、高三个剂量组和地塞米松组均能显著抑制二甲苯所致的小鼠耳廓肿胀和醋酸所致的小鼠腹腔毛细血管通透性增高(P<0.05),对大鼠棉球肉芽肿组织增生的炎症模型也有明显的抑制作用(P<0.05),且左旋紫草素高剂量组作用接近地塞米松组.结论:左旋紫草素对急性和亚急性炎症动物模型均有明显的对抗作用,这一作用可能是其作为抗炎药物应用的药理学基础.  相似文献   

6.
本实验用半胱胺经口给药方法诱发大鼠十二指肠球部溃疡。在离体条件下,以肠电慢波的频率和振幅为指标,观察了溃疡时十二指肠各部位的电活动变化。结果表明:(1)溃疡病变均选择牲地形成在十二指肠球部,溃疡中心在离幽门括约肌0.5cm左右处;(2)在幽门括约肌尾侧0.5cm处(形成溃疡部位)和1.0cm及2.0cm处(未形成溃疡部位)的溃疡大鼠十二指肠电慢波频率,均明显地高于对照组(P<0.05)而其振幅的变化不甚明显(P>0.05);(3)在幽门括约肌尾侧1.0cm处,十二指肠球部穿孔性溃疡大鼠的电慢波振幅明显地大于单纯性溃疡大鼠(P<0.05),而在幽门括约肌尾侧2.0cm处,穿孔性溃疡大鼠的电慢波频率明显高于单纯性溃疡大鼠(P<0.05)。以上结果提示:由半胱胺诱发的十二指肠球部溃疡对十二指肠电慢波频率有加速作用,并随溃疡病变的加重,十二指肠电慢波活动似有增强倾向。  相似文献   

7.
为探讨天麻成分对羟基苯甲醛的抗血小板聚集作用,本实验以二磷酸腺苷(ADP)、花生四烯酸(AA)、血小板活化因子(PAF)为诱导剂,探讨了对羟基苯甲醛的体外抗血小板聚集活性;采用ADP静脉注射致小鼠肺栓塞方法以及下腔静脉结扎致大鼠静脉血栓方法,考察了对羟基苯甲醛的体内抗血小板聚集活性;并对经口给药的对羟基苯甲醛的急性毒性进行了检测。结果表明,天麻成分对羟基苯甲醛对ADP诱导的家兔体外血小板聚集有明显的对抗作用,其半数抑制率(50%inhibitory concentration,IC50)为2mmol/L,对PAF诱导的家兔体外血小板聚集无明显影响;天麻成分对羟基苯甲醛能明显降低小鼠肺栓塞死亡率,并显著对抗大鼠下腔静脉血栓的形成。说明天麻成分对羟基苯甲醛在体外、体内均具有显著的抗血小板聚集活性。急性毒性研究结果表明天麻成分对羟基苯甲醛经口给药的小鼠半数致死量(lethal dose 50,LD50)为1.23 g/kg。  相似文献   

8.
侧脑室注射蛙皮素可显著地减轻消炎痛造成的大鼠胃粘膜损伤,并呈明显的剂量-效应关系。蛙皮素在抑制溃疡发生的同时,还明显地抑制消炎痛对胃酸分泌的刺激作用,并增加胃壁结合粘液的分泌。这些作用可能与其抗溃疡效应有关。 切除胃交感神经对溃疡发生及蛙皮素减轻溃疡的作用均无影响;切除双侧膈下述走神经可显著地减轻溃疡,但在切除迷走神经大鼠,蛙皮素的保护作用较在完整动物降低,且低于仅切除迷走神经效应。或甚至较切除前加重。此外,将具有兴奋迷走中枢作用的促甲状腺激素释放激素(TRH)注入侧脑室可明显地加重溃疡,并可对抗蛙皮素减轻溃疡的作用。这些结果仅提示,蛙皮素的抗溃疡作用可能部分地通过它对迷走中枢紧张性的抑制。 将蛙皮素(0.3μg)注入大鼠下丘脑前核或腹内侧核,可明显地减轻溃疡;而注入下丘脑后核则无效。这提示,前两个核团可能是蛙皮素在中枢有效作用部位的组成部分。  相似文献   

9.
济元阳口服液主要药效实验研究   总被引:2,自引:0,他引:2  
以济元阳口服液7g/kg、14g/kg灌胃,使小鼠性器官、副性器官重量显著增加,去势大鼠副性器官亦有增加;小鼠附睾精子数量增加,精子活率提高,并能对抗环磷酰胺所致精子数量与活力下降,雄性小鼠及去势大鼠交配能力均有增强;肾阳虚小鼠体重、胸腺指数上升,自由活动、游泳耐力及耐寒能力均有所增强,以上实验结果表明,济元阳口服液有补肾壮阳、生精长力之功效。  相似文献   

10.
大鼠脑内5-羟色胺在应激性溃疡形成中的作用   总被引:9,自引:0,他引:9  
杨红  张席锦 《生理学报》1985,37(5):416-424
通过神经化学和神经药理学的方法,在大鼠观察了冷冻加束缚应激性溃疡的形成过程中,脑内5-羟色胺(5-HT)的作用。结果如下:1.在应激过程中,脑内5-HT 及其主要代谢产物5-羟吲哚乙酸(5-HIAA)的含量明显升高,特别是5-HIAA 的含量随着应激时间的延长持续上升,说明5-HT 的代谢加快。2.脑内5-HT 或5-HIAA 含量在应激45min 时与溃疡指数呈明显的负相关,而在应激180min 时则与溃疡指数呈明显的正相关。3.侧脑室注射5-HT或其前体5-羟色氨酸(5-HTP),对应激性溃疡的形成呈双重作用,小剂量时减轻而大剂量时加重溃疡的形成。4.腹腔注射5-HT 合成阻断剂对氯苯丙氨酸(pCPA)可降低大鼠脑内5-HT 和5-HIAA 含量,使应激60min 鼠的溃疡形成加重,而使应激180min 鼠的溃疡形成减轻。以上结果提示,在大鼠的冷冻加束缚应激性溃疡的形成过程中,脑内5-HT 起着一定的作用,它很可能在应激早期减轻而在应激晚期加重溃疡的形成。  相似文献   

11.
12.
High heterozygosity and tetrasomic inheritance complicate studies of asexually propagated polyploids, such as potato. Reverse genetics approaches, especially mutant library construction, can be an ideal choice if a proper mutagenesis genotype is available. Here, we aimed to generate a model system for potato research using anther cultures of Solanum verrucosum, a self‐compatible diploid potato with strong late blight resistance. Six of the 23 regenerants obtained (SVA4, SVA7, SVA22, SVA23, SVA32, and SVA33) were diploids, and their homozygosity was estimated to be >99.99% with 22 polymorphic InDel makers. Two lines—SVA4 and SVA32—had reduced stature (plant height ≤80 cm), high seed yield (>1,000 seeds/plant), and good tuber set (>30 tubers/plant). We further confirmed the full homozygosity of SVA4 and SVA32 using whole‐genome resequencing. These two regenerants possess all the characteristics of a model plant: diploidy, 100% homozygosity, self‐compatibility, and amenability to transgenesis. Thus, we have successfully generated two lines, SVA4 and SVA32, which can potentially be used for mutagenesis and as model plants to rejuvenate current methods of conducting potato research.  相似文献   

13.
We studied the effect of a mouse seminal vesicle autoantigen (SVA) on BSA-stimulated functions of mouse sperm. Uncapacitated, capacitated, and acrosome-reacted stages of sperm were morphologically scored, and the cellular zinc content was examined cytologically in a modified Tyrode solution at 37 degrees C for 80 min. More than 85% of control cells remained uncapacitated. Addition of 0.3% SVA to the cell incubation did not affect the cell status. Approximately 65% of cells were capacitated in the incubation medium containing 0.3% BSA. Only 30% of the cells became capacitated after incubation with 0.3% BSA and 0.3% SVA together. The decapacitation effect by 0.3% SVA could be subdued by more than 3% BSA in the cell incubation. Whereas BSA did, SVA did not cause removal of Zn(2+) from sperm, but SVA could suppress the BSA effect. The tyrosine phosphorylated proteins in sperm were detected after incubation in a modified HEPES medium containing 0.3% BSA and/or 0.3% SVA at 37 degrees C for 90 min. Whereas BSA enhanced greatly, SVA did not cause phosphorylation of proteins in the range of M:(r) 40 000-120 000. The BSA-stimulated protein tyrosine phosphorylation could be suppressed by SVA in the cell incubation.  相似文献   

14.
SINE-VNTR-Alu (SVA) elements are non-autonomous, hominid-specific non-LTR retrotransposons and distinguished by their organization as composite mobile elements. They represent the evolutionarily youngest, currently active family of human non-LTR retrotransposons, and sporadically generate disease-causing insertions. Since preexisting, genomic SVA sequences are characterized by structural hallmarks of Long Interspersed Elements 1 (LINE-1, L1)-mediated retrotransposition, it has been hypothesized for several years that SVA elements are mobilized by the L1 protein machinery in trans. To test this hypothesis, we developed an SVA retrotransposition reporter assay in cell culture using three different human-specific SVA reporter elements. We demonstrate that SVA elements are mobilized in HeLa cells only in the presence of both L1-encoded proteins, ORF1p and ORF2p. SVA trans-mobilization rates exceeded pseudogene formation frequencies by 12- to 300-fold in HeLa-HA cells, indicating that SVA elements represent a preferred substrate for L1 proteins. Acquisition of an AluSp element increased the trans-mobilization frequency of the SVA reporter element by ~25-fold. Deletion of (CCCTCT)(n) repeats and Alu-like region of a canonical SVA reporter element caused significant attenuation of the SVA trans-mobilization rate. SVA de novo insertions were predominantly full-length, occurred preferentially in G+C-rich regions, and displayed all features of L1-mediated retrotransposition which are also observed in preexisting genomic SVA insertions.  相似文献   

15.
Successful fertilization is tightly regulated by capacitation and decapacitation processes. Without appropriate decapacitation regulation, sperm would undergo a spontaneous acrosome reaction which leads to loss of fertilization ability. Seminal plasma is known to negatively regulate sperm capacitation. However, the suppressive mechanisms still remain unclear. In this study, we demonstrate the decapacitation mechanism of mouse seminal vesicle autoantigen (SVA) might target membrane sphingomyelin (SPM) and regulate plasma membrane Ca2+‐ATPase (PMCA) activity. The SVA was shown to suppress sperm capacitation induced by a broad panel of capacitation factors (bovine serum albumin (BSA), PAF, and cyclodextrin (CD)). Furthermore, SVA significantly decreased [Ca2+]i and NaHCO3‐induced [cAMP]i. Cyclic AMP agonists bypassed the SVA's suppressive ability. Importantly, the SVA may regulate PMCA activity which was evidenced by the fact that the SVA decreased the [Ca2+]i and intracellular pH (pHi) of sperm; meanwhile, a PMCA inhibitor (carboxyeosin) could reverse SVA's suppression of [Ca2+]i. The potential target of the SVA on membrane SPM/lipid rafts was highlighted by the high binding affinity of SPM–SVA (with a Kd of ~3 µM) which was close to the IC50 of SVA's suppressive activity. Additionally, treatment of mink lung epithelial cells with the SVA enhanced plasminogen activator inhibitor (PAI)‐1 expression stimulated by tumor growth factor (TGF)‐β and CD. These observations supported the membrane lipid‐raft targeting of SVA. In summary, in this paper, we demonstrate that the decapacitation mechanism of the SVA might target membrane sphingolipid SPM and regulate PMCA activity to lower [Ca2+]i, thereby decreasing the [cAMP]i level and preventing sperm pre‐capacitation. J. Cell. Biochem. 111: 1188–1198, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

16.
17.
L1 elements are the only active autonomous retrotransposons in the human genome. The nonautonomous Alu elements, as well as processed pseudogenes, are retrotransposed by the L1 retrotransposition proteins working in trans. Here, we describe another repetitive sequence in the human genome, the SVA element. Our analysis reveals that SVA elements are currently active in the human genome. SVA elements, like Alus and L1s, occasionally insert into genes and cause disease. Furthermore, SVA elements are probably mobilized in trans by active L1 elements.  相似文献   

18.
Mammalian sperm gain the ability to fertilize an egg successfully by the capacitation process. An unregulated capacitation process causes sperm to undergo a spontaneous acrosome reaction (AR) and resulting in loss of their fertilization activity. Thus, functional sperm activation is tightly regulated by a capacitation and suppression (decapacitation) mechanism. Factors, such as platelet-activating factor (PAF) present in both sperm and the female genital tract, are able to stimulate sperm capacitation. Seminal plasma is thought to have the ability to suppress sperm capacitation; however, the regulatory mechanisms of seminal plasma protein on sperm capacitation are not well understood. Recently, we demonstrated that seminal vesicle autoantigen (SVA), a major seminal vesicle secretory protein, is able to suppress mouse sperm capacitation. To further study the suppression spectra of SVA on sperm capacitation, we investigated the effect of SVA on PAF-induced mouse sperm capacitation-related signals. Here, we demonstrate that SVA decreases the [Ca(2+)](i) to suppress the PAF's effects on [Ca(2+)](i), the cAMP level, protein tyrosine phosphorylation, and capacitation. The inhibition of PAF-induced protein tyrosine phosphorylation and capacitation by SVA can be reversed by cAMP agonists. Characterization of the interactions of SVA with PAF by TLC overlay and tryptophan fluorescence spectrum analyses indicates that SVA is capable of binding PAF with an apparent dissociation constant K(d) > 50 microM. Together with these results, we demonstrate that SVA deceases [Ca(2+)](i) and cross-talks with PAF-induced intracellular signals to regulate mouse sperm capacitation.  相似文献   

19.
给小鼠灌服苦刺总生物碱盐酸(苦碱)能增强小鼠对常压密闭缺氧的耐受力,对抗异丙肾上腺素加速整体小鼠耗氧速度和降低低氧条件下的氧利用能力,也能对抗酚妥拉明降低小鼠在缺氧条件下的氧利用能力。苦碱还能延长断头小鼠的张口动作持续时间,以及氰化钾、亚硝酸钠和利多卡因中毒时的小鼠存活时间,表现出广谱的抗缺氧作用,且呈现量效关系。  相似文献   

20.
Morphological modification using solvent vapor annealing (SVA) provides a simple and widely used fabrication option for improving the power conversion efficiencies of solution‐processed bulk heterojunction (BHJ) small molecule solar cells. Previous reports on SVA have shown that this strategy influences the degree of donor/acceptor phase separation and also improves molecular donor ordering. A blend composed of a dithienopyrrole containing oligothiophene as donor (named UU07) and [6,6]‐phenyl‐C61‐butyric acid methyl ester as acceptor is investigated with respect to SVA treatment to explore the dynamics of the BHJ evolution as a function of annealing time. A systematic study of the time dependence of morphology evolution clarifies the fundamental mechanisms behind SVA and builds the structure–property relation to the related device performance. The following two‐stage mechanism is identified: Initially, as SVA time increases, donor crystallinity is improved, along with enhanced domain purity resulting in improved charge transport properties and reduced recombination losses. However, further extending SVA time results in domains that are too large and a few large donor crystallites, depleting donor component in the mixed domain. Moreover, the larger domain microstructure suffers from enhanced recombination and overall lower bulk mobility. This not only reveals the importance of precisely controlling SVA time on gaining morphological control, but also provides a path toward rational optimization of device performance.  相似文献   

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