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1.
目的:观察阿司匹林(aspirin)溶液对离体蟾蜍心脏心率和心肌收缩力的影响。方法:根据斯氏蛙心插管方法,用不同浓度的阿司匹林对离体蟾蜍心脏进行灌流,采用BL-410生物机能实验系统记录心率和心肌收缩力的变化。结果:灌注0.1g/ml的阿司匹林溶液时,离体蟾蜍的心脏收缩力明显下降和心率明显减慢(P0.05),心脏甚至停止跳动,0.05g/ml的阿司匹林溶液时,离体蟾蜍的心脏收缩力降低和心率减慢程度不如0.1g/ml,并且随着阿司匹林浓度的降低离体蟾蜍的心脏收缩力和心率降低程度逐渐较少。结论:阿司匹林溶液降低离体蟾蜍心肌收缩力和减慢心率,并随着阿司匹林浓度升高,其心肌收缩力和心率降低程度更加明显。 相似文献
2.
实验采用离体心脏灌流方法,观察了腺苷,腺苷受体特异性阻断DPCPX以及非特异性腺苷受体阻断剂茶碱对两栖类动物蟾蜍的离体心脏力和心率的影响。结果显示,腺苷对心脏收缩力和心率有明显的剂量依赖性抑制作用。单纯的DPCPX或茶碱对心肌收缩力和心率无显著影响,但在含腺苷的灌流液中加入DPCPX或茶碱后,对腺苷有明显的拮抗效应。 相似文献
3.
研究60%乙醇提取的马尾松花粉多糖组分D(PPM60-D)及其硫酸酯化物(SPPM60-D)对小鼠脾脏B淋巴细胞增殖、细胞内游离钙离子浓度([Ca2+]i)及抗体生成的影响。水煮醇沉法提取得到粗多糖,乙醇分级沉淀得到60%乙醇沉淀多糖PPM60,SephacrylS-400HR分离纯化得到多糖组分D,用氯磺酸-吡啶法对组分D进行硫酸酯化,尼龙毛法分离B淋巴细胞,MTT法测定其增殖,荧光分光光度计测定B淋巴细胞[Ca2+]i,溶血空斑实验(PFC)和定量溶血分光光度(QHs)法测定B细胞抗体生成情况。结果显示,SPPM60-D相对于PPM60-D能更显著地提高B淋巴细胞的增殖以及[Ca2+]i(P〈0.011:经TAK-242、LY294002、U73122、低分子肝素、维拉帕米和2-APB抑制剂作用后,均可抑制SPPM60-D和PPM60-D所致的[Ca2+]i)升高(P〈0.05或P〈0.01);PFC和QHS检测证实,SPPM60-D对于促进B淋巴细胞的分化及抗体的生成有显著作用,而PPM60-D的作用较弱。以上研究表明,PPM60-D经过硫酸酯化改性后,活性明显提高,推测SPPM60-D可与B淋巴细胞上TOLL样受体4(TLR4)结合,通过TLR4-P13K-PLC—IP3R信号通路使钙库释放激活的钙通道(CRAC)打开,从而使[Ca2+]i)升高来激活B淋巴细胞,进而提高其体外增殖和抗体生成能力。 相似文献
4.
P物质(substance P,SP)既是一个局部作用激素、又是一个循环激素,在体内可对许多器官发挥作用,对心血管活动的调节具有重要影响,在这方面以对血管活动的影响研究较多,对心脏活动的影响报道较少,对其作用机制尚不十分清楚。本工作试图在蟾蜍离体心脏标本上观察SP对心脏活动的直接效应,并初步探讨其作用机制。 相似文献
5.
目的:观察咖啡碱对中华大蟾蜍离体坐骨神经干及离体心脏的影响;方法:采用细胞外电极引导法和离体心脏灌流法;结果:咖啡碱处理后,坐骨神经干动作电位幅度显著或极显著高于对照组(P<0.05,P<0.01);咖啡碱处理使心率明显加快,20mg/ml时显著增加心肌收缩力;结论:咖啡碱有兴奋神经及强心作用。 相似文献
6.
我们曾通过对比观察证明,饲喂低硒饲料两个月与注射黄嘌呤-黄嘌呤氧化酶3d对大鼠的影响相似,均能使心肌收缩功能减弱、谷胱甘肽过氧化物酶(GSH-Px)活性降低、脂质过氧化物(LPO)含量增多、电子自旋共振谱线面积增大。本实验沿用相同的低硒饲料与硒、锰添加量,在离体鼠心肌上,观 相似文献
7.
本文用离体心脏灌流技术研究了丁酸钠对~3H-乙酰基参入大鼠心脏细胞核纽蛋白的影响。用蔗糖梯度离心将大鼠离体灌流心脏的细胞核分为心肌的和非心肌的,分别提取组蛋白。尿素-丙烯酰胺凝胶电泳将组蛋白分为五个组分。其比放射性测定的结果表明,~3H-乙酰基只参入核心组蛋白,程度为H_3>H_(2b)>H_4>H_(2a)。Triton-尿素-丙烯酰胺凝胶电泳图放射自显影结果显示,无论心肌细胞核还是非心肌细胞核,在丁酸钠为1m mol/L情况下,组蛋白H_3又可见三个亚组分(H_(3_1)、H_(3_2)及H_(3_3)),H_4可分出四个亚组分(H_(4_1)、H_(4_2)、H_(4_3)及H_(4_4));其总组蛋白乙酰化程度减低至对照组数值的60%。“冷追击”实验的结果提示,丁酸钠引起高乙酰化组蛋白的积蓄,确是通过其对组蛋白脱乙酰基过程的抑制作用而实现的。 相似文献
8.
目的 研究丹酚酸B对离体大鼠工作心脏血流动力学的影响.方法 采用Langendorff离体心脏灌流的方法,以左室内压( LVSP)、左室舒末压(LVEDP)、室内压最大上升速率(+dp/dtmax)、室内压最大下降速率(- dp/dtmax)、心率(HR)等血流动力学参数为指标,观察丹酚酸B对心肌收缩性能的影响.结果 不同剂量(10、5、2.5 mg/L)的丹酚酸B可使LVSP、±dp/dtmax明显升高,同时使HR减慢,并呈剂量依赖性,但对LVEDP无明显作用.结论 丹酚酸B对离体工作心脏有剂量依赖性正性肌力作用. 相似文献
9.
牛磺酸对蟾蜍离体心脏活动及蝌蚪抗缺氧能力的影响 总被引:3,自引:0,他引:3
研究牛磺酸对蟾蜍离体心脏活动及蝌蚪抗缺氧能力的影响。结果表明 :在气温为 (2 0± 1)℃时 ,浓度为 5g·L- 1 ,10g·L- 1 的牛磺酸任氏液使离体心脏跳动时间明显延长 (p <0 .0 5 ) ,浓度为 1g·L- 1 、5g·L- 1 的牛磺酸水溶液对蝌蚪抗缺氧能力有极显著 (p <0 .0 1)、显著 (p <0 .0 5 )改善 相似文献
10.
吗啡对于蟾蜍离体脊髓的兴奋作用 总被引:1,自引:0,他引:1
在蟾蜍离体脊髓标本上,吗啡10~(-5)—10~(-3)M 能增大背根-腹根反射(DR-VRR),此增大作用不被纳洛酮拮抗,但10~(-4)M 的纳洛酮可轻度增大 DR-VRR。含菲核结构的阿片生物碱蒂巴因、可待因的兴奋作用强于吗啡,这三种药物在更高浓度时则抑制、甚至取消 DR-VRR。不含菲核结构的合成镇痛药美沙酮、哌替啶及脑啡肽类似物 FK33-824对 DR-VRR只起抑制作用。虽然吗啡能阻滞脊髓突触前抑制,并以可被纳洛酮逆转的方式取消刺激腹根诱发的背根电位(VR-DDRP),吗啡增大 DR-VRR 并非由于它的去抑制作用。本文结果提示,吗啡的兴奋作用与阿片受体无关,并为含菲核结构的阿片生物碱所特有。 相似文献
11.
Permeability of the Isolated Toad Bladder to Solutes and Its Modification by Vasopressin 总被引:18,自引:12,他引:18 下载免费PDF全文
Measurements have been made of the permeability of the isolated urinary bladder of the toad to a number of small solute molecules, in the presence and absence of vasopressin. Vasopressin has a strikingly specific effect on increasing permeability of the bladder to a group of small, uncharged amides and alcohols while penetration by other small molecules and ions is unaffected. The movement of urea is passive, as indicated by equal flux rates in the two directions. The reflection coefficients for chloride and thiourea indicate a high degree of impermeability of the bladder to these solutes even in the presence of large net movements of water. The low concentration of thiourea in the tissue water when this compound is added to the mucosal bathing medium indicates that the major permeability barrier to thiourea is at the mucosal surface of the bladder. The findings can be accounted for by a double permeability barrier consisting of a fine selective diffusion barrier and a porous barrier in series. The former would constitute the permeability barrier to most small solutes while the latter would be the rate-limiting barrier for water and the amides. It would be the porous barrier which is affected by vasopressin. Reasons are presented which require both barriers to be contained in or near the plasma membrane at the mucosal surface of the bladder. 相似文献
12.
Studies on the Movement of Water through the Isolated Toad Bladder and Its Modification by Vasopressin 总被引:17,自引:13,他引:17 下载免费PDF全文
Measurements of diffusion permeability and of net transfer of water have been made across the isolated urinary bladder of the toad, Bufo marinus, and the effects thereon of mammalian neurohypophyseal hormone have been examined. In the absence of a transmembrane osmotic gradient, vasopressin increases the unidirectional flux of water from a mean of 340 to a mean of 570 µl per cm2 per hour but the net water movement remains essentially zero. In the presence of an osmotic gradient but without hormone net transfer of water remains very small. On addition of hormone large net fluxes of water occur; the magnitude of which is linearly proportional to the osmotic gradient. The action of the hormone on movement of water is not dependent on the presence of sodium or on active transport of sodium. Comparison of the net transport of water and of unidirectional diffusion permeability of the membrane to water indicates that non-diffusional transport must predominate as the means by which net movement occurs in the presence of an osmotic gradient. An action of the hormone on the mucosal surface of the bladder wall is demonstrated. The effects of the hormone on water movement are most simply explained as an action to increase the permeability and porosity of the mucosal surface of the membrane. 相似文献
13.
黄芩苷对家兔离体子宫平滑肌的作用 总被引:1,自引:0,他引:1
目的:观察黄芩苷对家兔离体子宫平滑肌收缩的作用及其与Ca2+的关系.方法:制作常规离体家兔子宫平滑肌肌条,考察黄芩苷对子宫肌条反应的影响.结果:(1)黄芩苷(5-10mmol-L-1)剂量依赖抑制子宫平滑肌收缩;(2)黄芩苷对催产素及高K去极化液中Ca2+所致的离体子宫平滑肌收缩均呈剂量依赖性抑制;使CaC12累积量-效曲线非平行性右移,最大效应下降,呈非竞争性抑制;(3)且对子宫平滑肌依细胞内、外Ca2+两种收缩成分均呈抑制作用.结论:黄芩苷对家兔离体子宫平滑肌条的抑制作用,可能与其拮抗Ca2+有关. 相似文献
14.
目的:本研究采用小鼠离体十二指肠平滑肌观察姜黄素对胃肠道蠕动的影响,探讨其作用机制。方法:取小鼠离体十二指肠平滑肌条,放入37℃Krebs液浴槽中,通入95%氧气和5%二氧化碳混合气体,分组进行下列实验:对照组和分别加入10-40 M姜黄素组,测量记录十二指肠平滑肌的自主收缩变化;另取一组平滑肌条,分对照组、乙酰胆碱组、乙酰胆碱+姜黄素组、阿托品组、阿托品+姜黄素组,采用张力换能器连接多通道生理信号采集处理系统,测量比较十二指肠平滑肌舒缩的变化。结果:小鼠十二指肠平滑肌加入姜黄素孵育后,其自主收缩幅度有明显下降(P0.01),而且降低的幅度与姜黄素剂量相关;给与乙酰胆碱引起十二指肠收缩后,再加姜黄素孵育,十二指肠平滑肌的收缩幅度明显的下降(P0.01);给予阿托品引起小鼠平滑肌舒张后,再给予姜黄素孵育,平滑肌收缩幅度进一步降低。结论:姜黄素对小鼠离体十二指肠平滑肌具有直接舒张作用。 相似文献
15.
The Effect of Quinidine on Calcium Accumulation by Isolated Sarcoplasmic Reticulum of Skeletal and Cardiac Muscle 下载免费PDF全文
Franklin Fuchs Edward W. Gertz F. Norman Briggs 《The Journal of general physiology》1968,52(6):955-968
Quinidine potentiates twitch tension and (at higher concentrations) causes contracture of skeletal muscle whereas the same drug reduces tension development of cardiac muscle. To gain insight into the possible differences in the excitation-contraction coupling mechanism of the two types of muscle the effect of quinidine on calcium accumulation by isolated sarcoplasmic reticulum from skeletal and cardiac muscle was investigated. In a medium containing ATP, Mg++, oxalate, and 45Ca, pharmacologically active concentrations of the drug inhibited calcium accumulation by both skeletal and cardiac sarcoplasmic reticulum. The inhibition of the rates of calcium, uptake by the skeletal muscle preparation ranged from 11% with 10-4
M quinidine to 90% with 10-3
M quinidine. With the cardiac muscle preparation the inhibition ranged from 16% with 3 x 10-6
M quinidine to 100% with 10-3
M quinidine. With both preparations the inhibition of calcium transport was accompanied by an inhibition of the Ca++-activated ATPase activity of the sarcoplasmic reticulum. The effect of quinidine on the skeletal sarcoplasmic reticulum supports the hypothesis that this compound produces twitch potentiation and contracture by interfering with intracellular calcium, sequestration. Its effect on cardiac sarcoplasmic reticulum. has been interpreted in terms of the hypothesis that cardiac contractility is a function of the amount of calcium released from the sarcoplasmic reticulum which is in turn dependent upon the absolute calcium content of the reticulum. Hence, following inhibition of calcium transport there would be less calcium available for coupling. 相似文献
16.
Minseek Kim Seong-Hyeok Yang Hui-Gang Han Eunbi Kim Sinil Kim Youn-Lee Oh Hyeon-Su Ro 《Mycobiology》2022,50(5):374
In the mating of filamentous basidiomycetes, dikaryotic mycelia are generated through the reciprocal movement of nuclei to a monokaryotic cytoplasm where a nucleus of compatible mating type resides, resulting in the establishment of two different dikaryotic strains having the same nuclei but different mitochondria. To better understand the role of mitochondria in mushrooms, we created four sets of dikaryotic strains of Lentinula edodes, including B2 × E13 (B2 side) and B2 × E13 (E13 side), B5 × E13 (B5 side) and B5 × E13 (E13 side), E8 × H3 (E8 side) and E8 × H3 (H3 side), and K3 × H3 (K3 side) and K3 × H3 (H3 side). The karyotypes and mitochondrial types of the dikaryotic strains were successfully identified by the A mating type markers and the mitochondrial variable length tandem repeat markers, respectively. Comparative analyses of the dikaryotic strains on the mycelial growth, substrate browning, fruiting characteristics, and mitochondrial gene expression revealed that certain mitochondria are more effective in the mycelial growth and the production of fruiting body, possibly through the activated energy metabolism. Our findings indicate that mitochondria affect the physiology of dikaryotic strains having the same nuclear information and therefore a selection strategy aimed at mitochondrial function is needed in the development of new mushroom strain. 相似文献
17.
Physiological and Morphological Characteristics of Kurthia zopfii Isolated from Meat Products 总被引:3,自引:3,他引:0
G. A. Gardner 《Journal of applied microbiology》1969,32(3):371-380
18.
建立大鼠输精管平滑肌细胞的培养方法。取大鼠输精管,剥离外膜和内膜,用组织块法进行体外培养。用抗α-SMA(anti α-smooth muscle actin)免疫组化染色的方法鉴定培养的细胞。结果显示,在倒置显微镜下观察细胞形态多样,表现为长梭形或星形,细胞伸出突起互相接触,彼此融合,部分区域细胞多层重叠,部分区域细胞单层高低起伏,呈"峰-谷"状生长。免疫组化染色鉴定呈阳性反应,用该方法所分离、培养的输精管平滑肌细胞纯度达99%以上。应用组织块法培养大鼠输精管平滑肌细胞,操作简单,结果稳定。 相似文献
19.
Ouabain added to physiological salt solutions bathing the isolated frog retina irreversibly abolishes the electrical response to light (the electroretinogram or ERG). The time course of abolition depends on the concentration of ouabain in the medium and the surface of the retina to which it is applied. When the glycoside is placed on the receptor surface, in 7 min the ERG is completely eliminated by 10-4
M ouabain and more than 90% inhibited by 3 x 10-5
M ouabain. The effect is slower at lower concentrations and when the solution is applied to the vitreous surface of the retina. The evidence suggests that abolition of the ERG by ouabain is due principally to inhibition of the active transport of sodium: (a) Structurally modified glycosides which are considerably less potent inhibitors of alkali cation-activated ATPase activity in preparations of frog retinal outer segments are also poorer inhibitors of electrical activity in isolated retinas. (b) Replacing much of the sodium in the medium bathing the retina by choline, Tris, or sucrose significantly protects the retina from ouabain. It is suggested that in a standard sodium environment essentially constant activity of the sodium pump is required to prevent rapid and irreversible change. The cellular sites most critically dependent on the sodium pump have not been identified. 相似文献