Inhibition of uptake1 by (+)-oxaprotiline reveals a differential central regulation of noradrenaline and adrenaline release

Summary Inhibition of uptake, in the central nervous system leads to a decrease of sympathetic outflow to many tissues; central a2-adrenoceptors are involved in this decrease. The aim of the present study was to compare the effects of the selective uptake, inhibitor (+)-oxaprotiline on the plasma kinetics of noradrenaline and adrenaline in anaesthetized and in conscious rabbits. [³H]Noradrenaline and [^3H]adrenaline were infused iv. The arterial plasma concentrations of endogenous and radiolabelled noradrenaline and adrenaline were measured, and the clearance from and spillover into the plasma of noradrenaline and adrenaline were calculated.Results obtained in conscious and anaesthetized rabbits were similar. (+)-Oxaprotiline 0.2, 0.6 and 1.8 mg kg^–1 iv. dose-dependently reduced the clearance of [³H]noradrenaline from the plasma. The clearance of [³H]adrenaline was reduced less. The spillover of endogenous noradrenaline was decreased by up to 35%. In contrast, the spillover of adrenaline tended to be enhanced. Prazosin 0.1 and 1 mg kg^–1 was injected iv. in a second part of each experiment. It lowered the blood pressure and caused a marked increase in noradrenaline spillover but no increase or even a decrease in adrenaline spillover.The results are compatible with the following hypothesis. The sympathetic outflow from the central nervous system is subject to a twofold a-adrenoceptor-mediated modulation: -adrenoceptor-mediated inhibition and ₁-adrenoceptor-mediated excitation. In the control of the sympathetic outflow to many extra-adrenal tissues, the ₂-adrenergic inhibition prevails. Uptake₁ inhibitors depress sympathetic outflow to such tissues by enhancing the ₂-adrenergic inhibition. In the regulation of the sympathetic outflow to the adrenal medulla, in contrast, ₂-adrenergic inhibition and ₁-adrenergic excitation have a similar impact. Uptake, inhibitors, hence, cause little change in adrenaline release: the two opposing influences cancel out. Prazosin produces an increase in noradrenaline but not adrenaline release because the loss of the central ₁ sympathoexcitation attenuates at best slightly the baroreflex to most extra-adrenal tissues but dampens markedly the baroreflex to the adrenal medulla. Correspondence to B. Szabo at the above address     

中药地榆的性状及显微鉴定

研究国内来源于地榆属8个不同种、变种与变型的地榆及2种混淆品的生药性状、组织构造及其粉末的鉴别特征,并分别列出生药性状、组织构造及粉末特征的检索表。     

环丙沙星与氧氟沙星联用抗结核药物肝毒性比较

目的　研究环丙沙星或氧氟沙星联用抗结核药的肝毒性并探讨其机制。方法　分别测定异烟肼和利福平联合用药 (IR)组及其分别联用氧氟沙星 (IRO)或环丙沙星 (IRC)组小鼠的血清谷氨酸氨基转移酶 (ALT)、肝指数、肝匀浆丙二醛 (MDA)含量、肝微粒体细胞色素P45 0和线粒体Ca2 ATP酶活性 ,及肝病理检查 ,结果与对照组以及实验组之间进行比较。结果　与正常对照组比较 ,IR组及IRO组的血清ALT、肝细胞匀浆MDA明显增高 (P <0 .0 5 ) ,而IRC组变化不大 (P >0 .0 5 ) ;同时发现IR组和IRO组的肝微粒体细胞色素P45 0含量较高和线粒体Ca2 ATP酶活性较低 ,而IRC组则相反 ;病理检查IRO和IRC组肝细胞坏死程度稍轻但与IR组比较无明显差异。结论　氧氟沙星、环丙沙星不增加异烟肼和利福平联用肝毒性 ,且环丙沙星有一定的拮抗作用。     

女性输卵管结扎术后腰痛病机及医疗体育疗法

对女性输卵管结扎术后腰痛进行调查和病理分析 ,以中药配合医疗体育康复治疗术后腰痛 ,取得较好疗效 ,并提出预防措施。     

脂肝清对高胆固醇血症家兔模型脂质代谢影响的实验研究

目的: 明确中药脂肝清对高脂血症防治作用,探讨其作用机制。方法: 以饲喂高脂饲料复制高胆固醇血症家兔模型,观察血清和肝脂质代谢,并且采用脂肝清进行预防实验,同时与一类降脂药洛伐他汀 (Lovastatine)作对照。结果: 1)中药明显降低血清TC、LDL C、TC/HDL C比值 (P<0.01或P<0.05),降低血清氨基转移酶活力 (P<0.01).2)中药明显降低肝TC、TG及LDL C含量。结论: 脂肝清具有调整血清脂质代谢,促进肝组织中脂质的排泄及保护肝功能等作用。     

蒙药广枣总黄酮对大鼠离体心脏功能的影响

目的：探讨广枣总黄酮(TFC)对心功能的影响。方法：采用Langendorff灌流法．用多导生理记录仪测定大鼠离体心脏的心率、心肌收缩力及心电图的变化。结果：TFC使正常灌流的大鼠离体心脏心电图的P—R问期延长．心率减慢．心肌收缩力增强;对缺氧灌流所导致的心率减慢和心脏收缩力减弱均呈明显的对抗作用。结论：TFC可改善心功能。     

临床常用药物对人体酸碱平衡的影响

目的：探讨临床常用药物对人体酸碱平衡的影响,指导临床工作。方法：用酸度计测定九种药品ｐＨ值,计算氢离子浓度。结果：偏碱性的药物有５０ｇ／Ｌ碳酸氢钠,谷氨酸钠、谷氨酸钾注射液;偏酸性的药物有盐酸精氨酸、维生素Ｃ、各种浓度葡萄糖注射液、氯化钠注射液。结论：临床上一些常用药品会影响人体的酸碱平衡,尤其在机体酸碱平衡调节发生障碍的情况下,更应谨慎。     

朱丹溪善用风药治疗血证谈

复习朱丹溪有关医学文献 ,阐发其应用风药治疗血证的机制 ,主要有 :风药直接止血 ;风药升阴散火止血 ;风药散火解毒、凉血止血 ;风药炒黑止血 ;风药振脾益气止血 ;祛除致病因素 ;其它。     

中西医结合防治围化疗期消化道损伤

目的：寻找化疗诱导胃肠粘膜损伤的保护方法。方法：对荷Ｈ２２腹水癌小鼠化疗前后分别给与健脾益气中药、肠生态制剂（以岐杆菌和地衣芽直菌）、中西医结合（中药和肠生态制剂联合）方法防治消化道损伤。检测胃肠膜病理,用流式细胞仪检测Ｈ２２腹水癌细胞凋亡,ＭＴＴ比色法检测杀伤作用,骨髓图片检测骨髓增生相。结果：中西医结合组较单纯化疗组对胃肠粘膜有保护作用明显增强化疗对Ｈ２２腹水癌细胞的杀伤和促进凋亡,减轻胃肠粘