Cholinergic control of gastric acid secretion

Summary In the perfused stomach preparation of the anaesthetized rat the cholinergic agonists acetylcholine (ACh) and bethanechol stimulated gastric acid secretion. Both agonists produced similar maximal acid output (70 mol/15 min) when infused intravenously. However, bethanechol was more potent, eliciting half maximal stimulation at 1.98 mol/kg/h. Secretory responses to either agonist were antagonized in a dose related fashion by blockade of muscarinic receptors with atropine. In contrast, inhibition of nicotinic receptors with hexamethonium produced a striking potentiation of ACh stimulated secretion whilst the bethanechol elicited secretion remained unaffected. In the presence of full nicotinic receptor blockade the ACh response curve was shifted to the left sixfold, half maximal stimulation being produced at 1.79 mol/kg/h. Cimetidine partially inhibited the secretory responses elicited by either ACh or bethanechol while blockade of adrenoceptors ( and ) did not affect acid output induced by cholinergic agonists. Secretion elicited by ACh is interpreted as being the composite effect of prosecretory action and an inhibitory mechanism due to the activation of nicotinic receptors. Hexamethonium, through nicotinic receptor blockade, inhibits the restricting mechanism and thus reveals the full stimulatory action of ACh.     

药用辅料在制剂中的应用概述

药用辅料是药物制剂的基础材料的重要的组成部分,在制剂型和生产中起着关键作用,它不仅赋予药物一定剂型,并且与提高药物的疗效,降低毒副作用有很大的关系,因此,研究开发,合理应用辅仅可提高药物制剂质量和生产技术水平,而且可取得较大的社会及经济效益。     

吗啡增强备用根大鼠脊髓后角组织提取液对培养鸡胚背根节的促神经突起生长的作用

用组织培养方法，探讨备用很大鼠手术侧和非手术侧脊髓后角组织提取液对鸡胚背根节（ＤＲＧ）神经突起的促生长作用，以及应用吗啡对此作用的影响。结果显示：备用根大鼠手术侧脊髓后角组织提取液作用的ＤＲＧ神经突起密度（３６．４２±４．６９），比非手术侧的（２３．９６±３．４７）明显增大。提示去初级传入纤维的脊髓后角组织具有促进ＤＲＧ神经突起生长的神经营养活性作用。应用吗啡的备用根大鼠手术侧脊髓后角组织提取液作用的ＤＲＧ神经突起密度（６４．１９±９．２４），又比备用根大鼠手术侧的大。这表明，吗啡具有进一步增强去初级传入纤维支配的脊髓后角组织提取液促进培养的ＤＲＧ神经突起生长的效应。     

腺苷脱氨酶抑制剂对氧反常大鼠心脏的保护作用

本文观察到腺苷脱氨酶抑制剂EHNA对离体灌流大鼠心脏氧反常性损伤有明显的作用,此外还发现在缺氧期(无氧灌流30分钟)EHNA也表现出明显的保护作用,心脏收缩幅度的降低和静息张力的升高均显著低于对照组。表明在缺氧期也可能有自由基的产生。     

The Study of Passive Membrane Properties and Morphology Reveals Neuronal Differences Along the Sagittal Axis of the Ventral Periaqueductal Grey Matter

The membrane properties of the neurons located in the ventral part of the periaqueductal grey (PAG) of the guinea-pig were studied using an in vitro slice preparation. Cells had low values of resting membrane potential (-53.3 +/- 1.3 mV, mean +/- standard error), high input resistance (195. +/- 16.2 M ohm) and moderate values of membrane time constant (12.6 +/- 0.7 ms). The last two parameters changed as recordings were made along the sagittal axis, higher values corresponding to the more rostral cells. Three main neuronal types-fusiform, triangular and stellate-were found in the ventral PAG using intracellular injection of Lucifer yellow. A study of the cell number and cell density was carried out in coronal and sagittal sections of the ventral PAG. This analysis showed a clear gradient of size in this region arising from the gradual disappearance of large (17 to 40 microm) neurons in the caudorostral direction. The neuronal density also increased in this direction. Therefore, some electrotonic and morphological parameters differ along the sagittal axis. These findings suggest a larger neuronal heterogeneity of the caudal part of the PAG, and might contribute to a functional segregation of this region.     

Dual action of angiotensin II on coronary resistance in the isolated perfused rabbit heart

Summary We studied the functional role of angiotensin II (AII) receptor subtypes and vasodilatory endothelial autacoid release in response to AII in isolated perfused rabbit hearts. AII infusion induced biphasic changes in coronary perfusion pressure (CPP): an initial increase was followed by a decrease until a plateau was reached. At higher concentrations of AII (10 nmol/l) this plateau phase was lower than the initial CPP level. AII infusion elicited inverse changes in peak left ventricular pressure (LVP): coronary constriction was associated with a transient decline, and during the plateau phase LVP was clearly increased. AII also moderately augmented prostacyclin (PGI₂) release from the coronary vascular bed. The AII-induced changes in CPP, LVP, and PGI₂ release were effectively inhibited by the AT₁ receptor subtype antagonist ICI D8731 (30 nmol/l), but not by the AT₂ receptor antagonist CGP 42112 (30 nmol/l). The adenosine A₁ receptor antagonist 8-phenyltheophylline (0.1 mol/l) attenuated the decline in CPP following the constriction phase without affecting the changes in LVP during AII infusion. The cyclooxygenase inhibitor diclofenac (1 mmol/l) had no effect on the AII-induced changes in CPP, whereas the nitric oxide-synthase inhibitor N^G-nitro-L-arginine (30 mol/l) markedly potentiated the vasoconstriction but was without effect on the plateau phase of the response. In contrast to AII, the thromboxane analogue U46619 elicited sustained increases in CPP which were associated with slight decreases in LVP.In conclusion, AII induced a biphasic pressor response in the rabbit coronary vascular bed consisting of a transient vasoconstriction followed by a dilatation especially at higher concentrations of AII, an effect which was independent of the endothelial autacoids nitric oxide and PGI₂. The AII-induced dilatation probably reflected rapid desensitization of the coronary arterial smooth muscle to the constrictor effect, and the concomitant accumulation of vasodilatory metabolites such as adenosine, generated during the positive inotropic action of AII. All the effects of AII in the rabbit heart appeared to be mediated via the AT, receptor subtype localized on coronary endothelial and smooth muscle cells, as well as on cardiomyocytes.On leave from the Department of Biomedical Sciences, University of Tampere, P.O. Box 607, FIN-33101 Tampere, FinlandCorrespondence to: I. Pörsti     

Contribution of Monoamine Oxidase(MAO) to the Binding of Tertiary Basic Drugs in Isolated Perfused Rat Lung

The effect of tertiary basic drugs on mitochondrial MAO activity and the effect of MAO inhibitors (MAOIs) on basic drug accumulation in the isolated perfused rat lung were studied to clarify the role of MAO in drug binding to lung tissue. In the perfused lung preparation, the inhibition of MAO by basic drugs correlated well with their lipid solubilities and followed competitive kinetics. The inhibitory rank order (imipramine diphenhydramine > quinine > metoclopramide > procainamide) also correlated with their accumulation in the perfused lung. Moreover, MAOI treatment decreased the accumulation of basic drugs in the lung, and the potency of MAOIs to inhibit drug accumulation in the lung correlated with their MAO inhibitory activity. These results indicate that lung MAO has specific binding sites for basic drugs and may function as a drug reservoir.     

TTV核酸模板快速制备方法

目的 寻求建立适合大批量临床标本检测TT病毒（TTV）核酸快速制备方法,直接用于PCR扩增。方法 应用蛋白酶K裂解酚氯仿抽取法与直接快速裂解法,分别制备TTV核酸做PCR模板,用于TTV的聚合酶链反应的快速检测。结果 在30例非甲－非庚型肝炎血清和50例慢性乙型肝炎患血清,应用经典的蛋白酶K裂解酚氯仿抽取法和直接快速裂解法,分别制备TTV核酸模板,在相同条件下进行PCR扩增,结果两种制备方法的符合率为89％。结论 TTV是一种新发现的肝炎病毒,目前主要以实验室检测病毒核酸的存在为诊断依据,建立了具有快速、简便、适合大批量临床标本中TTV核酸制备方法,对TTV肝炎的快速诊断,具有重要的意义。     

复方辛夷滴鼻液的研制与临床应用

目的：对复方辛夷滴鼻液的工艺和质控标准进行了研究。方法：通过改进工艺,采用提取挥发油和煎煮相结合的方法。结果：该法工艺合理、质量可靠,所制滴鼻液对治疗鼻炎疗效高,有效率达８６．３％。结论：可用该法制备复方辛夷滴鼻液,并应用于临床。     

血液分离胶的制备研究

目的 :对血液分离胶的制备进行研究。方法 :用天然橡胶和特效触变剂等原料制备具有触变性的凝胶 ,研究该凝胶分离血清的较优组成。结果 :血液分离胶的较优组成是天然橡胶 12 .8%、特效触变剂 2 8.0 %和溶剂汽油 5 8.2 %。结论 :所制备的血液分离胶具有制备容易、分离效果好和成本较低等优点。