N-Phenylethyl Amitriptyline in Rat Sciatic Nerve Blockade

Background: The antidepressant amitriptyline is commonly used orally for the treatment of chronic pain, particularly neuropathic pain, which is thought to be caused by high-frequency ectopic discharge. Among its many properties, amitriptyline is a potent Na+ channel blocker in vitro, has local anesthetic properties in vivo, and confers additional blockade at high stimulus-discharge rates (use-dependent blockade). As with other drug modifications, adding a phenylethyl group to obtain a permanently charged quaternary ammonium derivative may improve these advantageous properties.

Methods: The electrophysiologic properties of N-phenylethyl amitriptyline were assessed in cultured neuronal GH3 cells with the whole cell mode of the patch clamp technique, and the therapeutic range and toxicity were evaluated in the rat sciatic nerve model.

Results: In vitro, N-phenylethyl amitriptyline at 10 [mu]m elicits a greater block of Na+ channels than amitriptyline (resting block of approximately 90%vs. approximately 15%). This derivative also retains the attribute of amitriptyline in evoking high-degree use-dependent blockade during repetitive pulses. In vivo, duration to full recovery of nociception in the sciatic nerve model was 1,932 +/- 72 min for N-phenylethyl amitriptyline at 2.5 mm (n = 7) versus 72 +/- 3 min for lidocaine at 37 mm (n = 4; mean +/- SEM). However, there was evidence of neurotoxicity at 5 mm.     

血清HBsAg阳性对常见肾脏疾病的影响

血清ＨＢｓＡｇ阳性对常见肾脏疾病的影响郑祖德叶宁（南京市儿童医院，南京２１０００８）关键词ＨＢｓＡｇ；免疫检测；肾炎；儿童笔者就我院１９８９—１９９４年住院患有急性肾炎、过敏性紫癜性肾炎（简称紫癜性肾炎）、肾病综合征者共１９８例病儿的临床观察及免疫...     

卡介苗预防接种引起的腋下淋巴结炎 6 例报告

卡介苗预防接种引起的腋下淋巴结炎６例报告泉州市儿童医院郑建都１９９２年９月至１９９６年１０月共收治卡介苗预防接种引起的腋下淋巴结炎６例，现报告如下。一、一般资料６例中男４例，女２例；年龄２～８个月。６例均行卡介苗预防接种，接种部位为左上臂三角肌区，接...     

穴位封闭治疗脚鸡眼288例报告

方法取患足“内庭”,“昆仑”穴,常规皮肤消毒,用2％奴夫卡因5ml 加肾上腺素2滴,在穴位上直刺1～2cm 深,待有酸麻胀感后,每个穴位注入2.5ml。一般1周后鸡眼处变软,色泽变暗,半月后鸡眼自行脱落。除多次手术不愈和多发鸡眼需1周后重复穴位封闭外,其余均可1次治愈。若1周后鸡眼处无变软,色泽变暗者可封闭第二次。笔者用此法一共治疗152人,288个鸡眼中,1次治愈180个,2次治愈40个,3次以上治愈20个。     

软骨损伤的基因治疗研究进展

由于软骨组织内无血管,因此其损伤后仅靠其自身来修复是非常有限的.有研究表明,很多细胞因子具有促进软骨形成及软骨样组织修复的功能.由细胞介导的相关基因于损伤部位分泌这些细胞因子促进软骨修复被认为足最理想的治疗方法.基因治疗正是在这一基础上发展起来的一种治疗技术,近年来取得了快速的发展.就近期软骨损伤的基因治疗进展进行综述.     

General Anesthetics Do Not Affect Release of the Neuropeptide Cholecystokinin from Isolated Rat Cortical Nerve Terminals

Background: General anesthetics inhibit evoked release of classic neurotransmitters. However, their actions on neuropeptide release in the central nervous system have not been well characterized.

Methods: The effects of representative intravenous and volatile anesthetics were studied on the release of sulfated cholecystokinin 8 (CCK8s), a representative excitatory neuropeptide, from isolated rat cerebrocortical nerve terminals (synaptosomes). Basal, elevated KCl depolarization-evoked and veratridine-evoked release of CCK8s from synaptosomes purified from rat cerebral cortex was evaluated at 35[degrees]C in the absence or presence of extracellular Ca2+. CCK8s released into the incubation medium was determined by enzyme-linked immunoassay after filtration.

Results: Elevation of extracellular KCl concentration (to 15-30 mm) or veratridine (10-20 [mu]m) stimulated Ca2+-dependent CCK8s release. Basal, elevated KCl- or veratridine-evoked CCK8s release was not affected significantly by propofol (12.5-50 [mu]m), pentobarbital (50 and 100 [mu]m), thiopental (20 [mu]m), etomidate (20 [mu]m), ketamine (20 [mu]m), isoflurane (0.6-0.8 mm), or halothane (0.6-0.8 mm).