山楂醇提取物对大鼠离体胃、肠平滑肌条收缩性的影响

目的:考察山楂醇提取液对大鼠离体胃、肠平滑肌的影响.方法:本研究以大鼠的离体胃、肠平滑肌条为模型,考察在正常克氏液条件下加入山楂提取液大鼠胃、肠平滑肌条收缩状况.同时观察乙酰胆碱、阿托品作用下加入山楂提取液大鼠肠平滑肌条收缩状况.结果:山楂醇提取液在5-20mg生药/ml浓度范围内可显著抑制大鼠胃、肠平滑肌条的运动,且具有明显剂量依赖性.山楂醇提取液(20mg生药/ml)可拮抗乙酰胆碱引起的胃肠平滑肌的强烈收缩,山楂醇提取液(20mg生药/ml)可对抗阿托品引起的肠平滑肌的舒张作用.结论:山楂醇提取液对大鼠胃、肠平滑肌条的收缩具有明显的抑制作用.     

运动对大鼠血管平滑肌大电导钾通道生物物理特性的影响

对大鼠进行不同强度的游泳训练以建立动物模型,应用膜片钳技术分析训练1～4周以及对照组的大鼠血管平滑肌细胞大电导钾通道(BK通道)的门控．实验结果显示,BK通道的开放概率在游泳训练第2、3周时明显升高,到第4周趋于稳定;游泳训练后,通道对膜电位、胞内钙离子的敏感性显著增加,通道的平均开放时间常数增大,关闭时间常数减小．实验结果还显示,由游泳训练导致的被动牵张并不改变通道的电导．BK通道在被动牵张力作用下生物物理特性的变化,可能有缓解由于游泳训练而导致血压升高的作用,进而使机体保持正常的生理状态．     

焦山楂醇提物对大鼠离体胃、肠平滑肌条收缩性的影响

目的:观察焦山楂醇提取液对大鼠离体胃、肠平滑肌的影响.方法:本研究以大鼠的离体胃、肠平滑肌条为模型,观察在正常克氏液条件下加入焦山楂醇提取液后大鼠胃、肠平滑肌条收缩状况.同时观察乙酰胆碱、阿托品作用下加入焦山楂提取液对大鼠胃、肠平滑肌运动的影响.结果:焦山楂醇提取液在4-8 mg生药/ml浓度范围内可显著抑制大鼠胃、肠平滑肌条的运动,且具有明显剂量依赖性.焦山楂醇提取液(8mg生药/ml)可拮抗乙酰胆碱引起的胃肠平滑肌的强烈收缩和阿托品引起的肠平滑肌的舒张作用.结论:焦山楂醇提取液对大鼠胃、肠平滑肌条的收缩具有明显的抑制作用.     

前列腺素E1对大鼠离体胃平滑肌运动的作用

前列腺素Ｅ＿１对大鼠离体胃平滑肌运动的作用瞿颂义,李伟,郑天珍（兰州医学院生理学教研室兰州７３００００）胃平滑肌细胞合成的多种前列腺素（ＰＧ）调节着胃的运动,能使固体食物的排空减慢、液体食物的排空加快。为此我们取大鼠胃各部位的平滑肌条,观察其对ＰＧＥ...     

氢溴酸高乌甲素对小肠平滑肌运动的作用

目的：研究氢溴酸高乌甲素对小肠平滑肌运动的影响并探讨其可能的作用机制。方法：记录氢溴酸高乌甲素对家兔离体小肠平滑肌运动的影响,并测定氢溴酸高乌甲素处理后小鼠小肠推进运动的变化。结果：氢溴酸高乌甲素抑制家兔离体小肠平滑肌收缩的发展张力。纳洛酮对氢溴酸高乌甲素的肠肌抑制作用无明显影响（P〉0.05）。乙酰胆碱（0.1 mg/L）可使家兔小肠舒张末张力明显增加。氢溴酸高乌甲素处理后,乙酰胆碱对肠肌舒张末张力的增加百分比降低（P〈0.05）。氢溴酸高乌甲素对小鼠小肠推进运动有显著抑制作用（P〈0.05）。结论：氢溴酸高乌甲素对小肠平滑肌收缩有抑制作用,并可以部分阻断乙酰胆碱的肠肌收缩作用,阿片受体可能不参与该抑制作用。     

18β-甘草次酸对Wistar大鼠脑微动脉平滑肌细胞间缝隙连接的影响

目的：探讨18β-甘草次酸对Wistar大鼠脑微动脉平滑肌细胞间缝隙连接的影响,为寻求强效和可逆的缝隙连接阻断剂提供实验依据。方法：去除脑微动脉段外层结缔组织后,应用全细胞膜片钳技术,观察不同种类的缝隙连接阻断剂对Wistar大鼠脑微动脉段上平滑肌细胞膜电容（Cinput）、膜电导（Ginput）和膜电阻（Rinput）的影响。结果：（1）Wistar大鼠脑微动脉段上平滑肌细胞Cinput高于消化分离的单个平滑肌细胞。（2）18β-甘草次酸（18pGA）能浓度依赖性的抑制Wistar大鼠脑动脉平滑肌细胞间的缝隙连接,IC50分别为2．0μM。当18βGA100μM时,Wistar大鼠脑微动脉段上平滑肌细胞的Cinput、Ginput或Rinput与单个平滑肌细胞十分接近。结论：1813GA可以浓度依赖性的抑制Wistar大鼠脑微动脉平滑肌细胞间缝隙连接。     

胆汁对空肠平滑肌条运动影响的实验研究

目的:观察胆汁对兔离体小肠平滑肌的影响并初步探讨其作用机制.方法:取兔空肠纵行肌条,安置在各恒温灌流肌槽中并用BL-310生物技能实验系统记录空肠平滑肌条的收缩活动.结果:胆汁显著降低兔空肠肌条张力, 减小其收缩波平均振幅及收缩频率,并有剂量依赖关系.结论:胆汁对空肠肌条收缩活动具有明显的抑制作用,这种抑制作用部分经由肾上腺素能α受体及前列腺素介导,并有壁内神经节的参与.     

磁化黄连素药液对小鼠肠推进运动的影响

目的：探讨磁化黄连素药液对小鼠肠推进运动的影响。方法 实验分未磁化药液对照组、0.1T磁化药液组及0．25T磁化药液组,分剐用未磁化的炭末混悬黄连素药液、0.1T及0.25T磁化的炭末混悬黄连素药液对小鼠进行灌胃,30min后颈椎脱臼法处死小鼠,计算小鼠的肠炭束推进率。结果：磁化黄连素药液显增加小鼠的肠炭末推进率。结论 磁化黄连素药液显促进小鼠的肠推进运动。     

长期游泳运动对大鼠铁状态的影响

目的：观察不同的运动时间对铁状态的影响。方法：大鼠随机分为3、6、12个月的三个游泳运动组和相应安静组;运动期满后观察血液学铁状态指标和器官非血红素铁(NHI)含量和NHI总含量(TNHI)的变化。结果：与安静组相比,三种不同时间长度的运动均诱导一种具有血浆铁浓度降低、血浆转铁蛋白铁饱和度降低而血红蛋白浓度和红细胞比容得到雏持的血液学低铁状态;这种低铁状态伴有肝、脾、心、肾NHI浓度显著降低,但与运动时间无关;肝、脾和肾TNHI变化与其浓度变化方向一致,但心脏没有显著变化;上述器官TNHI随时间增加而增多。结论：尽管运动诱导的低铁状态类似于铁缺乏中期表现,但由于器官NHI重分布和铁贮存并没有进行性降低,因此,长期运动引起的低铁状态可能是机体内铁代谢对运动的适应,不存在所谓“运动性铁缺乏”现象。     

川芎嗪对大鼠胸主动脉平滑肌电压依赖性Cl-通道的影响

川芎嗪(即四甲基吡嗪tetramethylpyrazine)是从具有活血化淤兼有理气功用中药川芎中分离得到的一种生物碱,现已广泛应用临床,对治疗缺血性脑血管疾病、缺血性肢体血管疾病、部分泌尿系统疾病等有明显的疗效,安全而无明显的毒副作用.有作者报道川芎嗪有明显抑制α1-肾上腺受体激动所引起持续血管收缩,而使血管舒张作用,可能与其有类似的"钙通道阻断剂"作用有关.目前认为血管平滑肌的张力与钙、钾和氯通道有关,川芎嗪与钾和氯通道的关系目前未见报道. 1 材料与方法 (1)药物川芎嗪,无锡市第七制药厂生产;DMEM,DIDS,HEPES,胰蛋白酶,EGTA,硝苯地平(nifedipine),苯肾上腺素(简称PHE)均为 Sigma公司出品,其余试剂均为市场销售的分析纯试剂.均为美国Sigma公司产品;其余的试剂均为国产分析纯.     

Technique for cryopreservation of intestinal smooth muscle cells

Attempts were made to develop a simplified procedure for long-term cryopreservation of intestinal smooth muscle cells (ISMC). ISMC were collected from the ileum of Sprague-Dawley neonatal rats through cellular dissociation in trypsin. Cryopreservation method comprised of a rapid 1-step (protocol 1) and a slow 3-step (protocol 2) freezing of ISMC for 1 week. Preparations were thawed and single ISMC were assessed via the comet assay and damaged DNA was quantified through comet tail moment. The control unfrozen ISMC exhibited DNA damage of 2.34 ± 0.35 compared to ISMC cooled via protocol 2 (2.62 ± 0.36) and protocol 1 (10.15 ± 0.72). Thereafter, protocol 2 freezing method was adopted and ISMC were cryopreserved for 1-week, 1-month, and 4-months to analyse the temporal and long-term cryopreservation of ISMC. This revealed a DNA damage of 2.62 ± 0.36 (1-week), 3.81 ± 0.72 (1-month), and 5.1 ± 0.9 (4-months). Gradual cooling is suitable for continuing storage of ISMC and although fluctuation in cryoinjury is observed with time this is considered to reflect cell-to-cell variability.     

纳豆枯草杆菌培养滤液对家兔离体肠平滑肌的作用

目的观察纳豆枯草杆菌培养滤液（culture filtrate,CF）对家兔离体肠平滑肌的作用,并初步探讨其作用机制。方法制备兔离体回肠标本,分别记录肠平滑肌的正常收缩张力和收缩频率作为给药前对照,然后按累积剂量分别加入CF小剂量（每次0．2mL）、CF大剂量（每次0．5mL）、肉汤（每次0．5mL）,给药间隔3min,共给药8次,并描记收缩曲线。观察不同剂量cF对肠平滑肌的作用。另取肠段按毛果芸香碱、CF或阿托品、再毛果芸香碱的顺序给药,观察CF对M胆碱受体的作用。结果CF小剂量组在累积给药达1．6mL时,CF大剂量组在累积给药达3．5mL和4．0mL时,兔离体肠平滑肌收缩张力下降,与给药前比较差异有统计学意义（P〈0．05）,其余各点差异均无统计学意义（P〉0．05）。CF小剂量组在累积给药达1．2、1．4、1．6mL时,CF大剂量组在累积给药达4．0mL时,兔离体肠平滑肌收缩频率明显降低,与给药前比较差异有统计学意义（P〈0．05或P〈0．01）,其余各点差异均无统计学意义（P〉0．05）。CF或阿托品可明显对抗毛果芸香碱引起的兔离体肠平滑肌收缩张力的增加（P〈0．05或P〈0．01）,同时CF还能使其收缩频率明显减少（P〈0．01）。结论纳豆枯草杆菌CF能明显抑制兔离体肠平滑肌蠕动,其作用机制可能与阻断M胆碱受体有关。     

Cytotoxicity and genome-wide microarray analysis of intestinal smooth muscle cells in response to hexavalent chromium induction

Chronic ingestion of high concentrations of hexavalent chromium Cr(VI) in drinking water induces intestinal tumors in mice; however, information on its toxicity on intestinal smooth muscle cells is limited. The present study aimed to assess the in vitro and in vivo toxicological effects of Cr(VI) on intestinal smooth muscle cells. Human intestinal smooth muscle cells (HISM cells) were cultured with different concentrations of Cr(VI) to evaluate effects on cell proliferation ability, oxidative stress levels, and antioxidant system. Furthermore, tissue sections in Cr(VI) exposed rabbits were analyzed to evaluate toxicity on intestinal muscle cells in vivo. Gene chips were utilized to assess differential gene expression profiles at the genome-wide level in 1 μmol/L Cr(VI) treated cells. Intestinal tissue biopsy results showed that Cr(VI) increased the incidences of diffuse epithelial hyperplasia in intestinal jejunum but caused no obvious damage to the structure of the muscularis. Cell proliferation analysis revealed that high concentrations (≥64 μmol/L) but not low concentrations of Cr(VI) (≤16 μmol/L) significantly inhibited the growth of HISM cells. For oxidative stress levels, the expression of reactive oxygen species (ROS) and nitric oxide (NO) was elevated at high concentrations (≥64 μmol/L) but not at low concentrations of Cr(VI) (≤16 μmol/L). In addition, dose-dependent increases in the activity of oxidized glutathione (GSSH)/total-glutathione (T-GSH) were also observed. Gene chip screened 491 differentially expressed genes including genes associated with cell apoptosis, oxidations, and cytoskeletons. Some of these differentially expressed genes may be unique to smooth muscle cells in response to Cr(VI) induction.     

Hedgehog signaling controls homeostasis of adult intestinal smooth muscle

The Hedgehog (Hh) pathway plays multiple patterning roles during development of the mammalian gastrointestinal tract, but its role in adult gut function has not been extensively examined. Here we show that chronic reduction in the combined epithelial Indian (Ihh) and Sonic (Shh) hedgehog signal leads to mislocalization of intestinal subepithelial myofibroblasts, loss of smooth muscle in villus cores and muscularis mucosa as well as crypt hyperplasia. In contrast, chronic over-expression of Ihh in the intestinal epithelium leads to progressive expansion of villus smooth muscle, but does not result in reduced epithelial proliferation. Together, these mouse models show that smooth muscle populations in the adult intestinal lamina propria are highly sensitive to the level of Hh ligand. We demonstrate further that Hh ligand drives smooth muscle differentiation in primary intestinal mesenchyme cultures and that cell-autonomous Hh signal transduction in C3H10T1/2 cells activates the smooth muscle master regulator Myocardin (Myocd) and induces smooth muscle differentiation. The rapid kinetics of Myocd activation by Hh ligands as well as the presence of an unusual concentration of Gli sties in this gene suggest that regulation of Myocd by Hh might be direct. Thus, these data indicate that Hh is a critical regulator of adult intestinal smooth muscle homeostasis and suggest an important link between Hh signaling and Myocd activation. Moreover, the data support the idea that lowered Hh signals promote crypt expansion and increased epithelial cell proliferation, but indicate that chronically increased Hh ligand levels do not dampen crypt proliferation as previously proposed.     

Effects of micropatterned curvature on the motility and mechanical properties of airway smooth muscle cells

Geometric features such as size and shape of the microenvironment are known to alter cell behaviors such as growth, differentiation, apoptosis, and migration. Little is known, however, about the effect of curvature on cell behaviors despite that many cells reside in curved space of tubular organs such as the bronchial airways. To address this question, we fabricated micropatterned strips that mimic airway walls with varying curvature. Then, we cultured airway smooth muscle cells (ASMCs) on these strips and investigated the cells’ motility and mechanical properties using time-lapse imaging microscopy and optical magnetic twisting cytometry (OMTC). We found that both motility and mechanical properties of the ASMCs were influenced by the curvature. In particular, when the curvature increased from 0 to 1/150 μm⁻¹, the velocity of cell migration first decreased (0–1/750 μm⁻¹), and then increased (1/750–1/150 μm⁻¹). In contrast, the cell stiffness increased and then decreased. Thus, at the intermediate curvature (1/750 μm⁻¹) the ASMCs were the least motile, but most stiff. The contractility instead decreased consistently as the curvature increased. The level of F-actin, and vinculin expression within the ASMCs appeared to correlate with the contractility and motility, respectively, in relation to the curvature. These results may provide valuable insights to understanding the heterogeneity of airway constrictions in asthma as well as the developing and functioning of other tubular organs and tissue engineering.     

Fractalkine对大鼠肺动脉平滑肌细胞增殖的影响

目的：观察fractalkine（FKN）对体外培养的大鼠肺动脉平滑肌细胞（PASMCs）增殖的影响。方法：体外培养大鼠PASMCs,加入不同浓度（10-^10、10-^9和10-^8 mol／L）的FKN处理12h、24h和48h,采用四唑盐（MTT）法检测细胞增殖,流式细胞术（FCM）检测细胞周期。结果：MTT试验显示FKN显著促进大鼠PASMCs增殖,此作用呈浓度依赖性。FCM分析显示FKN使S期细胞比例和增殖指数P1值增加。FKN处理PASMCs 12h后,其S期细胞比例和H值即出现增加,24h达高峰。结论：FKN呈浓度依赖方式促进大鼠PASMCs增殖。     

Effect of motilin on the contractility of gastric smooth muscle via NO pathway in guinea pigs

This study investigates the gastroprokinetic effects of motilin and erythromycin A (EM-A) and its potential mechanism in guinea pigs Cavia porcellus in vitro. Guinea pig stomach strips were mounted under organ baths containing Krebs solution. Motilin,EM-A,Nω-Nitro-L-arginine (L-NNA),L-arginine (L-AA) were added to the bathing solution in a non-cumulative way. Then the effects of motilin and EM-A was studied during electrical field stimulation (EFS) in the absence and presence of L-NNA and L-AA in the gastri...     

A single-cell transcriptomic inventory of murine smooth muscle cells

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慢性吸烟大鼠气道平滑肌大电导的钙激活钾通道和Kv1.5表达的变化

复制大鼠的慢性吸烟模型,采用气道反应性的测定、HE染色、免疫组织化学染色、原位杂交和免疫印迹实验等方法,观察吸烟对大鼠支气管平滑肌大电导的钙激活的钾通道(BKca)和电压依赖性延迟整流钾通道Kv1．5蛋白和mRNA表达的影响,以阐明吸烟引起的气道高反应性发病机制中钾通道表达变化的作用。结果显示：(1)慢性吸烟可降低大鼠大气道和小气道BKca和Kv1．5蛋白和mRNA表达;(2)大气道BKca的降低程度大于Kv1．5,小气道BKca和Kv1．5的降低程度无明显差异：(3)吸烟对全肺组织BKca和Kv1．5的蛋白表达无明显影响。上述结果提示,慢性吸烟可下调大鼠气道平滑肌钾通道BKca和Kv1．5的表达水平,是导致气道高反应的机制之一。     

Ultrastructure of a molluscan smooth muscle during phasic contractions and in the relaxed state

Tension and X-ray diffraction patterns are not always correlated in the smooth anterior retractor muscle (ABRM) of Mytilus edulis. The muscle produces equatorial intensity profiles of X-ray diffraction patterns corresponding to either a relaxed or a contracted structure. During phasic contractions, comprising a contracted as well a a relaxed phase, the diffracted intensity on the equator at 0.003 A^?1 changes within the first 10s after onset of stimulation. The tension reaches a maximum after about the same time. The time dependence of this intensity change during phasic contraction has been measured. It shows that the tension decays within 10s, but the relaxed structure needs 30–40 s to reestablish. There is no difference between the observed intensities from the tonic and phasic contracted states. Inactivated muscles with minimum tension, normally termed relaxed, can have either a “contracted” or a relaxed structure.