Inhibition of nicotinic receptor-mediated catecholamine secretion by dryobalanops aromatica in bovine adrenal chromaffin cells

Effect of the aqueous extract from a medicinal plant Dryobalanops aromatica(Dipterocarpaceae) on catecholamine secretion was investigated in bovine adrenal chromaffin cells. The aqueous extract inhibited [(3)H]norepinephrine ([(3)H]NE) secretion induced by 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP), a nicotinic acetylcholine receptor (nAChR) agonist, with a half-maximal inhibitory concentration (IC(50)) of 8.4 +/- 1.7 microgml(-1). Increases in cytosolic calcium ([Ca(2+)](i)) and sodium ([Na(+)](i)) induced by DMPP were also inhibited by the extract. However, the binding of [(3)H]nicotine to nAChRs was not affected by the addition of the extract in receptor binding competition analysis, suggesting that active components in the extract and nicotine do not share the binding site in the nAChR. On the other hand, [Ca(2+)](i)increases induced by high K(+), ionomycin, bradykinin, angiotensin II, and thapsigargin were not inhibited by the extract. The data suggest that the extract from D. aromatica specifically inhibits catecholamine secretion by blocking nAChR in a noncompetitive manner.     

Melatonin and N-acetylserotonin inhibit leukocyte rolling and adhesion to rat microcirculation

The hormone melatonin produced by the pineal gland during the daily dark phase regulates a variety of biological processes in mammals. The aim of this study was to determine the effect of melatonin and its precursor N-acetylserotonin on the microcirculation during acute inflammation. Arteriolar diameter, blood flow rate, leukocyte rolling and adhesion were measured in the rat microcirculation in situ by intravital microscopy. Melatonin alone or together with noradrenaline did not affect the arteriolar diameter or blood flow rate. Melatonin inhibited both leukocyte rolling and leukotriene B₄ induced adhesion while its precursor N-acetylserotonin inhibits only leukocyte adhesion. The rank order of potency of agonists and antagonist receptor selective ligands suggested that the activation of MT₂ and MT₃ melatonin binding sites receptors modulate leukocyte rolling and adhesion, respectively. The effect of melatonin and N-acetylserotonin herein described were observed with concentrations in the range of the nocturnal surge, providing the first evidence for a possible physiological role of these hormones in acute inflammation.     

Subclassification of muscarinic receptors in the heart,urinary bladder and sympathetic ganglia in the pithed rat

Summary In pithed normotensive rats muscarinic receptors were characterized heart, urinary bladder and sympathetic ganglia; the selectivity of some classical muscarinic agents for these subtypes was investigated. The potencies in decreasing heart rate, increasing bladder pressure and increasing diastolic blood pressure were measured for the following, intraarterially administered cholinergic agonists: McN-A-343 ([4-m-chlorophenylcarbamoyloxy]-2-butynyltrimethylammonium), pilocarpine, carbachol, oxotremorine, arecoline, acetyl--methylcholine and acetylcholine. The selective M₁-antagonist pirenzepine, the mixed M₁/M₂-antagonist dexetimide and the cardioselective M₂-antagonist gallamine were used as tools for identification of the receptors. All data were obtained after intravenous pretreatment with a high dose of atenolol to eliminate tachycardia induced by stimulating sympathetic ganglionic muscarinic receptors.Dexctimide strongly antagonized the bradycardia as well as the increase in bladder pressure induced by pilocarpine, carbachol, oxotremorine, arecoline, acetyl--methylcholine and acetylcholine, whereas pirenzepine was much less effective. Gallamine antagonized the bradycardia, whereas no influence was found on the bladder contraction. Pilocarpine acted as a partial agonist in reducing heart rate as well as in increasing bladder pressure, whereas McN-A-343 was almost ineffective in doses up to 1 mg/kg.The hypertensive response to pilocarpine and carbachol was less pronounced than that produced by McN-A-343. Pirenzepine and dexetimide significantly antagonized the hypertensive response to McN-A-343 and pilocarpine, whereas gallamine was much less effective. The hypertensive response induced by carbachol was totally blocked by hexamethonium. The other agonists used in this study did not produce a significant increase in diastolic blood pressure in doses that produced a maximal effect on heart rate and urinary bladder pressure.Simultaneously, intraarterially infused acetylcholine dose-dependently and reversibly decreased the pressor response to intravenously administered McN-A-343.These data suggest that muscarinic receptors in rat sympathetic ganglia belong to the M₁-subtype, whereas the muscarinic receptors in rat heart and urinary bladder represent heterogenous populations of M₂-receptors. The agonists used in this study, though, could not discriminate between these heterogenous M₂-receptors.Like McN-A-343, pilocarpine appears to be a rather selective M₁-agonist. In this study the M₁/M₂ selectivity of muscarinic agents with pronounced M₂-agonist activity could not be evaluated since M₂-receptor stimulation interferes with the hypertensive response to M₁-receptor stimulation.     

Discrimination by N-ethylmaleimide between the chronotropic and inotropic response to muscarinic receptor stimulation in rat atrium

Summary N-ethylmaleimide (NEM) rapidly blocked the negative chronotropic effect of carbachol on rat right atrium. In contrast, NEM did not reduce the negative inotropic response to muscarinic (M) receptor stimulation. Carbachol inhibited the specific binding of [³H]-N-methylscopolamine ([³H]-NMS) to membranes of rat atria as reflected by a shallow inhibition curve. Both guanosine triphosphate (GTP) and NEM shifted the [³H]-NMS inhibition curves of carbachol to the right. Pretreatment of the atrial membranes with NEM abolished the GTP-induced rightward shift. However, when instead of the membranes the intact atria were pre-incubated with NEM, no interaction between NEM and GTP in the membranal preparation was observed. The results indicate that NEM sharply discriminated between the inotropic and chronotropic effects to M-receptor stimulation in rat atria. The inhibitory effect of NEM on the M-receptor-mediated negative chronotropic effect in rat atrium cannot be explained by an interaction of the sulfhydryl reagent with GTP-binding proteins, like N_i or N_o.     

Similarities and differences in the autonomic control of airway and urinary bladder smooth muscle

The airways and the urinary bladder are both hollow organs serving very different functions, i.e. air flow and urine storage, respectively. While the autonomic nervous system seems to play only a minor if any role in the physiological regulation of airway tone during normal breathing, it is important in the physiological regulation of bladder smooth muscle contraction and relaxation. While both tissues share a greater expression of M2 than of M3 muscarinic receptors, smooth muscle contraction in both is largely mediated by the smaller M3 population apparently involving phospholipase C activation to only a minor if any extent. While smooth muscle in both tissues can be relaxed by beta-adrenoceptor stimulation, this primarily involves beta2-adrenoceptors in human airways and beta3-adrenoceptors in human bladder. Despite activation of adenylyl cyclase by either subtype, cyclic adenosine monophosphate plays only a minor role in bladder relaxation by beta-agonists; an important but not exclusive function is known in airway relaxation. While airway beta2-adrenoceptors are sensitive to agonist-induced desensitization, beta3-adrenoceptors are generally considered to exhibit much less if any sensitivity to desensitization. Gene polymorphisms exist in the genes of both beta2- and beta3-adrenoceptors. Despite being not fully conclusive, the available data suggest some role of beta2-adrenoceptor polymorphisms in airway function and its treatment by receptor agonists, whereas the available data on beta3-adrenoceptor polymorphisms and bladder function are too limited to allow robust interpretation. We conclude that the distinct functions of airways and urinary bladder are reflected in a differential regulation by the autonomic nervous system. Studying these differences may be informative for a better understanding of each tissue.     

灵芝提取物抗肿瘤作用的实验研究

目的探讨一种灵芝提取物体内外抗肿瘤作用。方法应用小鼠H22肝癌移植瘤模型,研究灵芝提取物的体内抗肿瘤作用;采用MTT法检测灵芝提取物的体外抗肿瘤活性。结果①灵芝提取物对H22移植瘤呈剂量依赖性抑制作用,500 mg.kg-1组的瘤重抑制百分率达59.3%,与阴性对照组比较有统计学差异（P〈0.01）;②MTT法检测显示灵芝提取物对K562和HL60两种瘤株有较强抑制作用,对SMMC7221、HepG2、SW480、SW1116和SGC7901五种瘤株抑制作用较弱。结论灵芝提取物在体外及体内均有较强的抗肿瘤作用,其有效成分及机制有待进一步研究。     

Constituents of Laurus nobilis L. inhibit recombinant human lanosterol synthase

Extracts from 37 kinds of foods and foodstuffs were tested for inhibitory activity against recombinant human lanosterol synthase. Among them, extracts from five samples showed significant inhibition. Potent activity (55%) was found in 95% ethanol extract of Laurus nobilis L. Therefore, large-scale methanol extraction of the plant was carried out, and the constituents were separated by partition and fractionation by silica gel chromatography and HPLC. Four flavonoids, kaemperol 3-O-[2,4-O-di-E-p-coumaroyl--l-pyranorhamnoside] (1); 3,3,4,5,6,7,8-heptamethoxyflavone (2); 3,4,5,6,7,8-hexamethoxyflavone (nobiletin) (3); and 4,5,6,7,8-pentamethoxyflavone (tangeretin) (4); and six sesquiterpens, eremanthine (5), dehydrocostus lactone (6), costunolide (7), zaluzanin C (8), zaluzanin D (9) and reynosin (10) were isolated. Eremanthine (5) showed the most potent activity, 70% inhibition, at the concentration of 500 M.     

Effects of noradrenaline and neuropeptide Y on rat mesenteric microvessel contraction

We have studied the contractile effects of the sympathetic transmitter noradrenaline and its cotransmitter neuropeptide Y (NPY) given alone and in combination on isolated rat mesenteric resistance vessels (200–300 m diameter). Noradrenaline and NPY each concentration-dependently contracted rat mesenteric microvessels (EC₅₀ 800 nM and 10 nM, respectively), but noradrenaline caused considerably greater maximal effects than NPY (14.3 mN vs. 3.5mN). A low antagonistic potency of yohimbine indicated that the response to noradrenaline did not involve ₂-adrenoceptors, and the subtype-selective antagonists 5-methylurapidil, tamsulosin and chloroethylclonidine indicated mediation via an _1A-adrenoceptor. Shallow Schild regressions for prazosin and 5-methylurapidil indicated that an ₁-adrenoceptor subtype with relatively low prazosin affinity might additionally be involved. Studies with the NPY analogues PYY, [Leu³¹, Pro³⁴]NPY and NPY_18–36 demonstrated that NPY acted via a Y₁ NPY receptor. In addition to its direct vasoconstricting effects NPY also lowered the noradrenaline EC₅₀ but did not appreciably affect maximal noradrenaline responses indicating possible potentiation. The potentiating NPY response occured with similar agonist potency as the direct contractile NPY effects and also via a Y₁ NPY receptor. The Ca²⁺ entry blocker nitrendipine (300 nM) reduced direct contractile responses to noradrenaline and NPY but did not affect the potentiation response to NPY.     

2018—2020年郑州市第七人民医院血流感染分离菌的分布及耐药性分析

目的 了解血流感染分离菌的分布及耐药特征,为临床防治血流感染提供指导和依据。方法 收集2018年1月—2020年12月郑州市第七人民医院血培养分离的非重复菌株,采用WHONET5.6软件统计菌株的分布及耐药特征。结果 共分离546株菌株,革兰阴性菌302株（55.31%）,革兰阳性菌220株（40.29%）,真菌24株（4.40%）。前6位分离菌依次为凝固酶阴性葡萄球菌（CNS,23.44%）、大肠埃希菌（18.68%）、肺炎克雷伯菌（14.84%）、金黄色葡萄球菌（6.04%）、鲍曼不动杆菌（4.21%）和铜绿假单胞菌（3.85%）。大肠埃希菌对碳青霉烯类最敏感,肺炎克雷菌碳对美罗培南和亚胺培南的耐药率分别为30.86%和35.80%,鲍曼不动杆菌耐药较严重,耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）和耐甲氧西林金黄色葡萄球菌（MRSA）的检出率分别为72.66%、42.42%,未发现利奈唑胺和万古霉素耐药的葡萄球菌。结论 革兰阴性菌是医院血流感染的主要致病菌,细菌耐药情况复杂,临床要根据药敏结果合理选择抗菌药物。     

Genotyping and in vitro antifungal susceptibility of Neoscytalidium dimidiatum isolates from different origins

This study evaluated the genetic variability and in vitro susceptibility patterns of isolates of Neoscytalidium dimidiatum and Scytalidium hyalinum from different geographical origins. Partial sequences of four loci (the ITS region and D1/D2 domains of the 28S rRNA gene and the tubulin and chitin synthase genes) were analysed. Among a total of 1970 bp sequenced in 24 isolates, 7 polymorphic positions (0.36%) were detected, representing five different sequence types (ST1–ST5), from which two (ST2 and ST3) were detected exclusively in isolates from plants, two (ST1 and ST5) were found only in clinical isolates and one (ST4) was observed in isolates from humans and from a mango tree. We propose subordinating S. hyalinum as a variety of N. dimidiatum. Amphotericin B was the most active drug, but low minimum inhibitory concentrations were also detected for voriconazole, terbinafine and anidulafungin.     

The pharmacology of T-kinin and des-Arg(11)-T-kinin in primary cultures of rat bladder smooth muscle cells

T-kinin and its putative carboxypeptidase product des-Arg(11)-T-kinin are members of the kinin family that are unique to the rat. Primary cultures of rat bladder smooth muscle cells were used to investigate the pharmacology of these peptides. Calcium imaging experiments showed that rat bladder smooth muscle cells responded to both bradykinin and des-Arg(9)-bradykinin with an increase in [Ca(2+)](i) and responses to both agonists could be observed in the same cell. A more detailed pharmacological characterisation with a range of bradykinin receptor agonists and antagonists using 45Ca(2+) efflux confirmed the presence of both B(1) and B(2) bradykinin receptors. Using this cellular model, we confirm that T-kinin is a bradykinin B(2) receptor agonist and show for the first time that des-Arg(11)-T-kinin is a potent and selective bradykinin B(1) receptor agonist. In addition, using cells expressing the cloned rat and human bradykinin B(2) receptors plus the Ca(2+)-sensitive protein aequorin, T-kinin was shown to be selective for the rat over the human bradykinin B(2) receptor.     

闽产三叶青地上部分提取物体内抗炎镇痛作用研究

目的 研究闽产三叶青地上部分提取物体内抗炎镇痛作用。方法 分别采用低、中、高剂量的闽产三叶青地上部分提取物,抗炎作用实验以二甲苯致小鼠耳肿胀急性炎症模型并以醋酸泼尼松为阳性药、角叉菜胶致大鼠足肿胀急性炎症模型并以醋酸地塞米松为阳性药、大鼠棉球肉芽组织增生慢性炎症模型并以醋酸地塞米松为阳性药,镇痛作用实验以化学刺激法（扭体法）及热刺激法（热板法）并以罗通定为阳性药。结果 与模型组比较,闽产三叶青地上部分提取物中、高剂量组及粗提物组对二甲苯所致小鼠耳廓肿胀有明显的抑制作用（依次为P < 0.05,P < 0.01,P < 0.05）,耳肿胀抑制率分别为22.86%,38.79%,20.62%;提取物中、高剂量组及粗提物组对角叉菜胶致大鼠足肿胀急性炎症有明显的抑制作用（P < 0.05或P < 0.01）;提取物低、中、高剂量组及粗提物组均能显著减少大鼠棉球肉芽组织增生慢性炎症模型中大鼠肉芽肿的重量（依次为P < 0.05,P < 0.01,P < 0.01,P < 0.01）,其抑制率分别为28.12%,46.41%,59.58%,44.50%。与模型组比较,在60,90 min,提取物高剂量组能有效提高小鼠的痛阈值延长率（P < 0.05,P < 0.01）,痛阈值延长率最高达65.58%;提取物中、高剂量组及粗提物组能有效抑制醋酸致痛的小鼠扭体次数（依次为P < 0.05,P < 0.01,P < 0.05）,小鼠扭体潜伏期明显延长（依次为P < 0.05,P < 0.01,P < 0.05）,扭体次数明显减少（依次为P < 0.05,P < 0.01,P < 0.05）,镇痛抑制率最高达51.80%。结论 闽产三叶青地上部分提取物具有明显的体内抗炎镇痛作用。     

Effects of acetylcholine and atropine on the release of 14C-acetylcholine formed from U-14C-glucose in rat brain cortical and striatal prisms

Summary A perfusion technique has been used to study the mechanisms involved in the control of acetylcholine (ACh) release from rat brain cortical and striatal slices submitted to KCl depolarization. Tissues were superfused continuously with U-¹⁴C-glucose, a very efficient precursor of the acetyl moiety of ACh, and with eserine to prevent the hydrolysis of the ¹⁴C-ACh released in the superfusion medium.This radioenzymatic approach was more flexible than those in which endogenous ACh outflows were estimated using a biological or a radioenzymatic method. Moreover, the modulation of the ester release process could be studied using the physiological ligand of the presynaptic muscarinic receptor, i.e. ACh itself. The continuous synthesis of ¹⁴C-ACh from U-¹⁴C-glucose, throughout the superfusion experiment, allowed the rate of ¹⁴C-ACh release to reach a steady state, under resting conditions (5.6 mM KCl) as well as under conditions of stimulation by high concentrations of KCl. This method was very convenient for pharmacological studies as compared to other methods in which the efflux of ³H-ACh from performed intratissular stores of ³H-ACh was measured.Using this technique, it was shown that atropine (10 M) enhanced the rate of ¹⁴C-ACh spontaneous release. Curiously, extraneously added ACh (0.6 mM) had a similar effect. When cortical prisms were submitted to a brief 31 mM KCl pulse stimulation (3 min), the negative feedback regulation process was not fully triggered. Indeed, atropine, which prevents the interaction of the released ACh with the regulatory muscarinic receptor, significantly stimulated the ¹⁴C-ACh outflow only when brain tissues were submitted to a sustained 31 mM KCl depolarisation, or when the ACh concentration in the superfusion fluid was raised (0.6 mM). These results suggest that the muscarinic negative control of ACh release from brain cholinergic terminals becomes fully operative only when the nerve endings are depolarized and when the ACh concentration within the synapse exceeds a threshold, i.e. during intense functioning of the cholinergic synapse.Abbreviations AChE acetylcholinesterase - ChAc cholineacetyltransferase (EC 2.3.1.6)     

不同产地藤茶中二氢杨梅素含量及其与牛蒡子配伍的药效学研究

目的 探究不同产地、部位及加工工艺藤茶中二氢杨梅素含量的差异,及优选藤茶与牛蒡子配伍药效学研究。方法 二氢杨梅素高效液相方法学验证采用Agilent ZORBAX SB-C₁₈柱,流动相为甲醇-0.05 % 磷酸（30∶70）,流速为1 ml/min,检测波长为291 nm,柱温25 ℃。配伍药效验证方法采用大鼠棉球植入致炎及小鼠耳肿胀致炎模型,对大鼠棉球植入实验肉芽肿净量及小鼠耳肿胀率进行观察。结果 方法学验证二氢杨梅素在0.019 9～0.318 mg/ml范围内线性关系良好（r=0.999）,回收率在95.04 %～100.4 %之间,样品在24 h内稳定,该方法重复性较好。配伍药效学验证高剂量优选藤茶与牛蒡子配伍可致大鼠肉芽肿净量及小鼠耳肿胀率均显著低于空白对照组。结论 方法简便准确,二氢杨梅素在不同产地、部位及加工工艺中含量差异较大,其中以贵州省江口县自然晒干的芽尖部位藤茶含量最高。藤茶与牛蒡子配伍可显著改善咽部症状,减轻致炎程度,共同协同达到清咽效果。     

银杏叶及其提取物中33种禁用农药残留检测分析及风险评估

目的 建立银杏叶及其提取物中33种禁用农药残留的分析方法,并开展风险评估研究。方法 采用液相色谱-串联质谱法及气相色谱-串联质谱法对136批银杏叶及58批银杏叶提取物进行检测,采用点评估方式计算样品中农药残留的急性和慢性摄入风险,采用英国兽药残留风险排序矩阵计算各农药的风险得分。结果 136批银杏叶中共检出6种禁用农药,总检出率为35.29%,农药检出量为0.002～0.210 mg·kg^-1;检出农药的慢性膳食摄入风险为0.018%～0.620%,急性膳食摄入风险为0.000 1%～0.014 0%,表明银杏叶中农药的膳食暴露风险处于较低水平。58批银杏叶提取物中共检出2种禁用农药,检出率为55.17%,农药检出量为0.002～1.788 mg·kg^-1;检出农药的慢性膳食摄入风险为0.003%～0.143%,急性膳食摄入风险为0.002 4%,其膳食暴露风险也处于较低水平。风险排序结果表明,银杏叶中甲拌磷风险最高,应在生产和安全监管中重点关注。结论 该方法准确,重复性好,可用于银杏叶及其提取物中33种禁用农药的检测。测定结果显示,银杏叶及...     

Pre- and postsynaptic effects of p-tyramine and p-octopamine in the prostatic portion of the rat vas deferens

Summary The effects of p-tyramine and p-octopamine on the twitch responses of the prostatic portion of the rat vas deferens to electrical stimulation (0.025 Hz) were compared with the effects of noradrenaline. In tissues with normal monoamine oxidase (MAO) activity, the three amines increased the height and duration of the twitch contractions. When MAO activity was inhibited by pargyline (10 mol/l), p-tyramine and p-octopamine had mixed excitatory-inhibitory effects on the twitches, while noradrenaline had mostly excitatory effects along the whole range of concentrations assayed (0.158–15.8 mol/l). Selective blockade of ₁- and ₂-adrenoceptors, by corynanthine and yohimbine, respectively, showed that the excitatory effect of the amines depended on the activation of ₁-adrenoceptor and that the inhibitory action was related to the activation of ₂-adrenoceptors. Pretreatment with reserpine (5 mg/kg, 24 h; 2.5 mg/kg, 2 h before the experiment) largely prevented the effects of p-tyramine and p-octopamine, but the amines still modified the twitch responses to field stimulation. The addition of corynanthine and yohimbine to the bathing fluid revealed a considerable activation of ₁-excitatory and ₂-inhibitory adrenoceptors. Cocaine (10 mol/l) did not antagonize, but rather enhanced the inhibitory effects of p-tyramine and p-octopamine in tissues with normal contents of noradrenaline. Moreover, cocaine did not antagonize the inhibition caused by p-tyramine, and enhanced the inhibition induced by p-octopamine in the prostatic portion of the vasa deferentia from reserpine-pretreated animals. These results suggest that in this tissue, at least when MAO activity is inhibited, p-tyramine and p-octopamine behave similarly. The effects of both amines on the twitch contractions depend on the noradrenaline-releasing action of the compounds and, in addition, the compounds seem to activate adrenoceptors directly. Send offprint requests to S. M. Celuch at the above addressCareer Investigator on leave of absence from the Consejo de Investigaciones Científicas y Técnicas, ININFA, Junín 956, 5°P, RA-1113 Buenos Aires, Argentina     

中药败酱草的形态组织学研究——Ⅲ.菊科苦苣菜属、莴苣属和苦荬菜属植物

本文报道我国北方使用的来源于菊科植物的中药败酱草的生药形态组织学的研究结果,它们是:苣荬菜Sonchus arvensis L.S.、苦苣菜oleraceus L.圆耳苦苣菜S.asper (L.)Hill.紫花山莴苣Lactuca tatarica(L.)C.A.Mey.、中华苦荬菜Ixeris ccinensis(Thunb.)Nakai、抱茎苦荬菜I.sonchifolia Hance和苦荬菜I.denticulata(Houtt.)Stebb..文中附有生药组织图7幅以及上述生药的性状检索表和显微特征检索表.     

2018-2022年深圳市妇幼保健院分离真菌的分布及耐药情况分析

目的 调查分析南方医科大学附属深圳妇幼保健院分离真菌的分布特点和药物敏感性情况,为妇幼真菌感染疾病的临床诊治、耐药性监测和流行病学研究提供参考。方法 回顾分析南方医科大学附属深圳妇幼保健院2018年1月-2022年12月标本采集、真菌鉴定和抗真菌药敏试验的结果数据。结果 共分离真菌3 350株,前2位分别为白色念珠菌1 542株、光滑念珠菌223株。阳性标本以阴道分泌物/宫颈分泌物为主。妇科和产科分离到的真菌最多。白色念珠菌对伊曲康唑、伏立康唑的5年耐药率分别为9.58%、4.12%,对两性霉素B和5-氟胞嘧啶的5年敏感率分别为99.79%、98.01%,对氟康唑的历年敏感率有逐渐升高的态势。光滑念珠菌、近平滑念珠菌和热带念珠菌对两性霉素B及5-氟胞嘧啶的敏感率均为100.00%。克柔念珠菌对两性霉素B和伏立康唑100.00%敏感。结论 南方医科大学附属深圳妇幼保健院分离真菌以念珠菌属为主,其中白色念珠菌最多。阴道分泌物/宫颈分泌物是主要真菌阳性分离标本。白色念珠菌对两性霉素B的耐药率最低、敏感率最高,对伊曲康唑的耐药率最高、敏感率最低。光滑念珠菌、近平滑念珠菌、热带念珠菌和克柔念珠菌对两性霉素B和5-氟胞嘧啶均无耐药性。光滑念珠菌对伊曲康唑耐药率最高、敏感率最低。     

Cholinergic modulation of [3H]dopamine release from dendrosomes of rat substantia nigra

Summary Dendrosomes prepared from substantia nigra are able to take up and release [³H]dopamine in a Ca²⁺-dependent manner. The V_max values of [³H]dopamine uptake in substantia nigra dendrosomes was about 5 times lower than that in caudate putamen synaptosomes. The pattern of the K⁺-dependency of the [³H]dopamine release in substantia nigra dendrosomes was significantly different from that found in caudate putamen synaptosomes. The release of [³H]dopamine evoked by 15 mmol/l KCl from superfused dendrosomes was increased in a concentration-dependent manner by acetylcholine. The maximal potentiation produced by acetylcholine was about 40%. The potentiation of [³H]dopamine release by 10 µmol/l acetylcholine was insensitive to mecamylamine but antagonized by atropine and by pirenzepine. The effects of acetylcholine on the release of [³H]acetylcholine from substantia nigra nerve endings was also studied. Exogenous acetylcholine added to the superfusion medium decreased in a concentration-dependent manner the release of acetylcholine. This effect was not antagonized by mecamylamine or pirenzepine but fully antagonized by atropine. The data suggest the existence, in the substantia nigra of the rat, of two distinct muscarinic receptor subtypes regulating respectively dopamine release from dopamine dendrites and acetylcholine release from cholinergic nerve terminals.Part of this work was presented at a satellite meeting of the 11th International Congress of Pharmacology: Dopamine '90 held in Como, Italy (July 1990) Send offprint requests to M. Raiteri at the above address