粉防己碱对吗啡在离体豚鼠回肠中依赖性的作用

AIM: To evaluate the effects of tetrandrine (Tet) and nimodipine (Nim) on the morphine (Mor) withdrawal response in the isolated guinea pig ileum. METHODS: The withdrawal contracture was elicited by addition of naloxone (Nal) (1 mumol.L-1) to the isolated naive ileum incubated with Mor (3 mumol.L-1) at 37.5 degrees C for 4 h or to the ileum obtained from Mor-dependent guinea pig. RESULTS: When Nim (0.01, 0.05, and 0.1 mumol.L-1) or Tet (1, 10, and 50 mumol.L-1) was added 1 min before Nal in the naive ilea bathed in Krebs solution containing Mor, or when the ilea from Mor-dependent guinea pigs were incubated with Nim (0.01, 0.05, and 0.1 mumol.L-1) or Tet (1, 10, and 50 mumol.L-1) for 15 min, or when Nim (5 and 10 mg.kg-1, i.p.) or Tet (15 and 30 mg.kg-1, i.p.) was administered in vivo to Mor-dependent guinea pigs, the Nal-precipitated withdrawal contracture was significantly decreased in a dose-dependent manner. CONCLUSION: Tet and Nim, Ca2+ channel blockers, could inhibit the Nal-precipitated Mor withdrawal response in the isolated guinea pig ileum.     

粉防己碱对肺动脉平滑肌细胞钙激活钾通道的双重作用

目的：研究粉防己碱（Ｔｅｔ）对大鼠肺动脉平滑肌细胞钙激活钾（Ｋｃａ）通道的影响。方法 内面朝外膜片箝单通道记录法,结果：Ｔｅｔ７．５和１５μｍｏｌ．Ｌ＾－１使Ｋｃａ的开放概率由０．２５１±０．０１２增加到０．３４０±０．０１３和０．４１５±０．０１１（Ｐ〈０．０１）,关闭时间由（６１±１５）ｍｓ缩短到（３３±１０）和（２８±１１）ｍｓ（Ｐ〈０．０１）Ｔｅｔ３０μｍｏｌ．Ｌ＾－１使开放概率和开放时间     

粉防己碱对培养乳牛基底动脉平滑肌细胞内游离钙浓度的影响

目的：研究粉防己碱对培养乳牛基底动脉平滑肌细胞游离钙浓度（[Ca^2 ]i)的影响。方法：利用AR－CM－MIC阳离子测定系统,采用Fura 2-AM为指示剂,测量单个细胞内[Ca^2 ]i。结果：粉防己碱10－100μmol/L对培养乳牛基底动脉平滑肌细胞静息[Ca^2 ]i无明显影响。在细胞外钙为1．3mmol/L,粉防己碱可浓度依赖性地抑制KC1引起[Ca^2 ]i的升高。咖啡因10mmol/L可诱导一次[Ca^2 ]i瞬间快速升高,随后自发回复到静息水平,粉防己碱10和30μmol/L对咖啡因诱导的[Ca^2 ]i瞬间升高没有作用,但高浓度（100μmol/L）粉防己碱抑制了[Ca^2 ]i瞬间升高。在细胞外钙为1.3mmol/L,苯肾上腺素10μmol/L可引起双相[Ca^2 ]i变化,包括快速升高相和持续升高相。在细胞外钙为零,苯肾上腺素仅引起[Ca^2 ]i的快速升高相。粉防己碱可浓度依赖性地抑制苯肾上腺素引起[Ca^2 ]i快速升高相。结论：在培养乳牛基底动脉平滑肌细胞,粉防己碱可能通过影响电压依赖性和苯肾上腺素受体介导的钙通道而抑制钙内流。高浓度粉防己碱也可能影响肌浆网钙释放或钙摄取。     

粉防己碱抑制血管平滑肌细胞胶原合成

目的　观察粉防己碱(Tet)对血管壁胶原沉积和血管平滑肌细胞胶原蛋白合成的影响。方法　用羟脯氨酸含量反映主动脉胶原沉积状况,用[³H]-脯氨酸参入反映细胞胶原蛋白合成。结果　与伪手术组相比,肾血管性高血压大鼠主动脉壁羟脯氨酸含量明显增加;粉防己碱可有效降低主动脉壁胶原含量,并呈浓度依赖性抑制[³H]-脯氨酸参入AngII或NE诱导的血管平滑肌细胞。结论　粉防己碱抑制血管平滑肌细胞胶原合成和动脉壁胶原沉积是其逆转血管重构作用的重要机制之一     

粉防己碱对犬多种血管平滑肌的作用

观察了粉防己碱（Ｔｅｔ）对犬离体冠状动脉，脑基底动脉和肠系膜动脉平滑肌的作用。Ｔｅｔ３０μｍｏｌ·Ｌ－１对ＫＣｌ２０及６０ｍｍｏｌ·Ｌ－１去极化犬冠状动脉呈非内皮依赖性松弛。给格列本脱后，Ｔｅｔ仍可使冠状动脉松弛７４．５％．Ｔｅｔ可使ＫＣｌ所致冠状劝脉收缩的量效曲线右移，最大反应降低，ｐＤ２为４．４其－ｌｇＥＣ５０与其松弛苯福林引起的大肠系膜劝脉收缩的－ｌｇＥＣ５０相近，均为４．１Ｔｅｔ对ＫＣｌ所致犬基底动脉的收缩有明显松弛作风     

EMD_(56431)对豚鼠气管平滑肌的作用

目的　观测新型的ＡＴＰ敏感钾通道开放剂ＥＭＤ５６４３１（ＥＭＤ） 的平喘作用,并与钙通道阻滞剂粉防己碱（ｔｅｔｒａｎ ｄｒｉｎｅ,Ｔｅｔ）比较。方法　豚鼠离体气管法和整体药物引喘法。结果　ＥＭＤ 能抑制ＫＣｌ 所致豚鼠气管螺旋条的收缩反应,其抑制作用随［Ｋ＋］ｏ 浓度的增高而减弱;ＥＭＤ 能浓度依赖性地使氨甲酰胆碱和组胺的量效曲线右移,最大效应降低,均表现为非竞争性拮抗,ｐＤ′２ 值分别为４－４５ 和４－４０ ;组胺喷雾引起的豚鼠哮喘模型中,ＥＭＤ 灌胃能剂量依赖性地使豚鼠的引喘潜伏期延长,抽搐动物数亦随剂量增加而减少（ｎ ＝ ８ ,Ｐ＜ ０－０５）。结论　ＥＭＤ 的支气管扩张作用在于开放钾通道,其作用强于Ｔｅｔ,两者具有协同作用。ＥＭＤ 单用或与Ｔｅｔ 小剂量合用显示出较好的效果     

粉防己碱对犬缺血心肌的保护作用

粉防己碱（Ｔｅｔ）ｉｖ８００ｕｇ·ｋｇ－１可使麻醉犬血压—过性降低，与此同时对血流动力学诸项指标的影响较小。结扎犬冠脉后，能降低犬室颤的发生率及死亡率，降低缺血心肌丙二醛的形成，减少胞内ｃａ２＋的蓄积和ＣＰＫ的释放，以上结果表明，Ｔｅｔ对缺血心叽有良好的保护作用。     

粉防己碱对犬缺血心肌的保护作用

粉防己碱(Tet)iv800ug·kg^-1可使麻醉犬血压—过性降低,与此同时对血流动力学诸项指标的影响较小。结扎犬冠脉后,能降低犬室颤的发生率及死亡率,降低缺血心肌丙二醛的形成,减少胞内ca²⁺的蓄积和CPK的释放,以上结果表明,Tet对缺血心叽有良好的保护作用。     

Effects of neurotensin on isolated intestinal smooth muscles

The effects of neurotensin were investigated in intestinal smooth muscle preparations. Neurotensin relaxed the rat ileum, and contracted the guinea-pig ileum and taenia. Neurotensin induced a biphasic response (relaxation followed by contraction) in the contracted guinea-pig ileum. In all systems, half-maximal effects were obtained with 4–5 nM neurotensin and maximal responses with 30–60 nM; tachyphylaxis occurred with higher concentrations. Tetrodotoxin did not affect the responses to neurotensin in the rat ileum and the guinea-pig taenia. Tetrodotoxin abolished the contraction or the contraction phase (but not the relaxation phase) of the biphasic response induced by neurotensin in the guinea-pig ileum. Atropine partially inhibited the neurotensin-induced contraction in the guinea-pig ileum. These results suggest that neurotensin acts on intestinal smooth muscle both directly (relaxation of the rat and guinea-pig ileum, and contraction of the guinea-pig taenia) and through a nerve-mediated, partly cholinergic, process (contraction of the guinea-pig ileum).     

盐酸二氢埃托啡对小鼠、大鼠和豚鼠肠道平滑肌的作用

目的：研究ＤＨＥ对肠道平滑肌的作用。方法：小鼠、大鼠和豚鼠离体和在体肠道平滑肌上，以吗啡为对照，比较ＤＨＥ与吗啡对肠道平滑肌作用的异同。结果：吗啡和ＤＨＥ减慢小鼠肠推进运动的ＥＤ５０分别为２．７９ｍｇ·ｋｇ－１和３．２３μｇ·ｋｇ－１；ＤＨＥ３６～６０μｇ·ｋｇ－１ｓｃ可松弛小鼠在体肠道平滑肌，在相同的实验条件下，吗啡５～２０ｍｇ·ｋｇ－１ｓｃ可剂量依赖性地收缩小鼠在体肠道平滑肌；在小鼠、大鼠和豚鼠离体肠管上，ＤＨＥ兴奋肠道平滑肌的浓度依次为１０～１００，０．１～１０和１０～１００μｍｏｌ·Ｌ－１，吗啡兴奋肠道平滑肌的浓度分别为０．１～１０，０．００２～２．０和０．１～１０μｍｏｌ·Ｌ－１，而ＤＨＥ兴奋肠道平滑肌的浓度是在镇痛剂量下体内无法达到的。结论：对肠道平滑肌作用，ＤＨＥ与吗啡不同，ＤＨＥ呈舒张效应，而吗啡为收缩效应。     

甘草、白芍及合用对在体兔肠管运动的影响

甘草、白芍水提合剂(0.21g)对在体兔肠管平滑肌运动有明显的抑制作用,两者合用较单用效果好,降频率作用较降幅度作用强。给药后20min—25min降低兔肠管收缩频率分别为正常对照组的64.71％和70.5％,二者比较有显著性差异(P<0.05,),与阳性对照组阿托品(0.25mg)比较;给药后20min降低肠管收缩频率为阿托品的3.8倍。给药后20min—25min降低肠管收缩幅度分别为正常对照组的50.0％和63.67％,二者比较有显著差异(P<0.05;P<0.05),降低幅度为阿托品的1.21倍。结果表明:甘草、白芍水提剂对在体肠管的运动呈明显抑制作用。     

Effects of bradykinin and some of its fragments on smooth muscles and chemotaxis

Bradykinin (BK) and two of its C-terminal fragments, namely H-Phe-Ser-Pro-Phe-Arg-OH and H-Ser-Pro-Phe-Arg-OH were found to be potent inhibitors of the chemotaxis of rat polymorphonuclear neutrophils (PMN). The activity of the three peptides was significantly enhanced by SQ 14225, a rather specific inhibitor of kininase II. A shorter C-terminal sequence of BK (Phe-Arg-OH) was inactive. The whole peptide (BK) exerted potent actions on blood pressure and on isolated organs, e.g. the rabbit mesenteric vein or the guinea pig ileum, but none of its fragments showed similar effects. The present findings suggest that rat PMN possess membrane receptors which cannot be considered identical to B1- and B2-receptors, previously characterized on isolated smooth muscles.     

The effects of theophylline and cyclic AMP on intestinal smooth muscle contractions

The effects of 10^?4-10^?3 M theopphylline, cyclic 3'5'-adenosine monophosphate (cyclic AMP), dibutyryl cyclic AMP (DBC) and theophylline plus DBC were observed on the spontaneous and potassium (K)-induced contractions of the guinea-pig taenia coli. All of the compounds inhibited spontaneous contractions as well as the phasic and tonic components of the K-contracture. The effects of cyclic AMP, a compound which will not readily penetrate the cell membrane, were similar to those of the other compounds in inhibiting the spontaneous and phasic contractions, but it was a less effective inhibitor of the tonic contracture. Inhibition of spontaneous and phasic activity may occur at the cell membrane while the inhibitory actions on the tonic contracture may depend on cellular penetration by the inhibitor. There was no evidence that theophylline and DBC have different sites of action.     

The Binding of Cadmium Ions to the Smooth Muscle of Guinea-Pig Taenia Coli

Abstract: Taenia coli was used to study the property of binding of Cd²⁺. The Scatchard plots of cadmium uptake showed that two qualitative Cd²⁺ binding sites (high and low affinity binding sites) exist in taenia coli. Decrease in Ca²⁺ concentration in the medium did increase the cadmium binding. The Scatchard analysis of Cd²⁺ binding in taenia coli at 4° indicated a single class of binding sites (only high affinity binding sites). These findings suggest that the greater number of high affinity Cd²⁺ binding sites in taenia coli may relate to the binding to cell membrane. Further, it was postulated that some of low affinity binding sites in taenia coli may reflect intracellular accumulation, indicating the action on the contractile system.     

甘草、芍药合剂对离体兔肠管运动的影响

甘草、芍药水提合剂(GPM0.415g)对离体兔肠管运动呈明显抑制作用。降频率作用较降幅度作用为强。给药后5min,降低肠蠕动频率为正常对照组的60.88％与阿托品(0.25mg)对照组比较、降频率作用明显,且维持时间较长。给药后5～10min,降幅度作用两者相接近,给药后15min,幅度降低是阿托品组的1.15倍,但无显著性差异(P>0.05);给药后20min,降幅度作用则为阿托品的1.85倍,两者比较有显著性差异(P<0.01)。GPM亦能够拮抗氯化钡(BaCl_2),乙酰胆碱(Ach)、组织胺对离体兔肠平滑肌的兴奋作用。     

川芎嗪对离体兔血管平滑肌和豚鼠盲肠带的作用

目的：研究川芎嗪对离体兔血管平滑肌和豚鼠盲肠带的作用。方法：制备兔基底动脉环ＫＣｌ量－效曲线、ＣａＣｌ２致盲肠带收缩及兔门静脉条的自律性收缩。结果：川芎嗪非竞争性拮抗ＫＣｌ对兔基底动脉的收缩作用，其ＩＣ５０值为１．５１ｍｍｏｌ／Ｌ，抑制ＣａＣｌ２引起豚鼠盲肠带收缩的ＩＣ５０值为１９０μｍｏｌ／Ｌ，对兔门静脉条收缩也有抑制作用。结论：川芎嗪有钙通道阻滞作用。     

埃他卡林等三种结构类型的钾通道开放剂对非血管平滑肌舒张作用的选择性

目的:研究新结构类型的ATP-敏感性钾通道 (KATP) 开放剂 (KCO)、抗高血压新药埃他卡林 (iptakalim,Ipt) 对胃、回肠和膀胱等非血管平滑肌舒张作用的影响,并比较Ipt与其结构完全不同的KCO、氰胍类的吡那地尔 (pinacidil,Pin) 和苯并噻二嗪类的二氮嗪 (diazoxide,Dia)舒张作用的差异,为进一步明确Ipt舒张作用的选择性特征提供一定的依据.方法:采用大鼠离体胃底、回肠和膀胱肌条3种组织,以10-5 mol·L-1 乙酰胆碱预收缩,观察不同浓度的药物对它们的舒张作用.结果:Ipt 在10-8～10-4 mol·L-1范围内对3种组织均无显著的舒张作用;Pin在10-8～10-4 mol·L-1范围内对胃底条和膀胱平滑肌等均无显著的舒张作用,但在10-5和10-4 mol·L-1时对回肠的舒张率分为 28.8%和 51.9%,诱发显著的舒张作用;Dia对3种组织的作用与Ipt相似,均不引起明显的舒张作用.结论:Ipt不影响胃、回肠和膀胱的舒张作用,选择性优于Pin,与Dia相似;化学结构类型不同的KCO对回肠、胃和膀胱的作用既相似也有不同.