Effects of 4-aminopyridine on the turnover of monoamines in the central nervous system of the rat

Summary The effects of 4-aminopyridine (4-AP) on the turnovers of 5-hydroxytryptamine, dopamine and noradrenaline in the central nervous system of rats were studied by means of amine disappearance following inhibition of tryptophan or tyrosine hydroxylase. 4-AP (3 mg/kg i.p.) did not change the utilizations of 5-hydroxytryptamine or dopamine but it markedly accelerated that of noradrenaline in the brain and in the spinal cord. This stimulatory effect of 4-AP was completely dependent on nerve impulses since no effect was observed following an acute section of the noradrenaline nerves to the spinal cord. The effect of 4-AP was blocked by the-adrenoreceptor stimulating agent clonidine. Pentylenetetrazole, at a dose producing similar behavioural changes as 4-AP, caused only a slight stimulation of the noradrenaline turnover. 4-AP might enhance the flux of calcium ions into nerve terminals during depolarization, and thus increase the release of noradrenaline, whereas this process might be of less importance in the dopamine and the 5-hydroxytryptamine nerves.     

Dynamic aspects of peripheral nerve changes in progressive neural muscular atrophy

Summary Serial nerve biopsies were performed at an early, and at an advanced stage of the disease in 2 patients with progressive neural muscular atrophy. The early biopsy showed a complete loss of the large diameter and thickly myelinated fibres, as well as an expansion of the endoneurial interstitium in both cases. Myelinated and unmyelinated fibres exhibited axonal degeneration in all biopsies occasionally. Onion bulb formation, a typical feature of peripheral neuropathy in neural muscular atrophy, was found to be prominent only in the latter biopsies. As regards the formal pathogenesis of hypertrophic neuropathy in neural muscular atrophy, axonal dystrophy and interstitial changes of the endoneurium were regarded as primary phenomena, demyelination and onion bulb formation as secondary. A possible causal relation between axonal dystrophy and interstitial changes, observed in these cases, is discussed in the light of the present literature.

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Zusammenfassung Bei 2 Patienten mit progressiver neuraler Muskelatrophie wurden Nervenbiopsien jeweils in einem frühen und in einem fortgeschrittenerem Stadium der Erkrankung entnommen und verglichen. In beiden Fällen zeigten bereits die frühen Biopsien ein völliges Fehlen der großkalibrigen, dickbemarkten Axone. Ebenfalls als frühe Veränderung wurde eine Erweiterung des endoneuralen Interstitiums festgestellt. Eine geringe Anzahl der vorhandenen bemarkten und unbemarkten Axone in allen Biopsien wies degenerative Veränderungen auf. Die für die progressive neurale Muskelatrophie typische Zwiebelschalenbildung der Schwannschen Zellen — möglicherweise eine Reaktion auf wiederholte De-und Remyelinisierungsvorgänge um dystrophische Axone — trat erst in den späteren Biopsien deutlicher hervor. Hinsichtlich der formalen Genese der hypertrophischen Neuropathie bei neuraler Muskelatrophie sind nach diesen Beobachtungen axonale Dystrophie und interstitielle Veränderungen des Endoneuriums als primäre Entmarkung und Zwiebelschalenbildung als sekundäre Phänomene zu betrachten. Die Möglichkeit einer kausalen Beziehung zwischen axonaler Dystrophie und interstitiellen Veränderungen wird an Hand der vorliegenden Befunde und Literatur diskutiert.

     

Studies on the possible contribution of a peripheral presynaptic action of clonidine and dopamine to their vascular effects under in vivo conditions

Summary The functional consequences of drug-induced stimulation under in vivo conditions of -adrenoceptors and dopamine receptors at vascular adrenergic nerve endings (presynaptic receptors) was studied in the autoperfused hindquarters or hindlegs of cats anaesthetized with urethane. The changes in perfusion pressure in response to electrical stimulation of the lumbar sympathetic chain were taken as a measure of noradrenaline release from the vascular adrenergic nerves. Presynaptic inhibitory -adrenoceptors and dopamine receptors were activated by clonidine and dopamine, respectively. According to in vitro experiments these two drugs are more potent stimulants of peripheral presynaptic than postsynaptic receptors. The lowest frequency of stimulation of the lumbar sympathetic chain which yielded a reproducible pressor response was 4 Hz for the autoperfused hindquarters and 1 Hz for the hindlegs. Clonidine was tested over a wide dose range (1–100 g/kg i.v.). A reduction of the stimulation-induced pressor response in the autoperfused hindquarters or hindlegs was observed only after the rather high dose of 100 g/kg of clonidine. The inhibition was marked at low frequencies of stimulation (1–4 Hz) and weak or absent at high frequencies (16 and 32 Hz). The dose of clonidine (100 g/kg) which proved to be effective at presynaptic receptors produced a transient increase in blood pressure and in perfusion pressure of the hindquarters and hindlegs and virtually abolished spontaneous sympathetic nervous activity. In spinal cats, the clonidine-induced increases in blood pressure and perfusion pressure were very pronounced and of rather long duration. Thus, under in vivo conditions clonidine showed no selectivity for presynaptic -adrenoceptors in a blood-perfused vascular bed, and its presynaptic action was negligible as compared to its powerful central sympatho-inhibitory effect.Dopamine was constantly infused into the autoperfused hindquarters or hindlegs at increasing rates until a vasoconstriction due to stimulation of vascular (postsynaptic) -adrenoceptors occurred. The monoamine did not inhibit the stimulation-induced increases in perfusion pressure of the autoperfused hindquarters or hindlegs and, thus, an effect on presynaptic receptors was not found. The results underscore the importance of in vivo experiments for assessing the therapeutic significance of drug-induced stimulation of presynaptic receptors.Part of the results has been presented at the 16th Spring Meeting of the German Pharmacological Society in Mainz (Haeusler, 1975)     

纳洛酮治疗脑梗死的疗效观察

目的　观察纳洛酮治疗脑梗死的疗效。方法　将 2 6 0例脑梗死患者随机分组 ,治疗组 12 8例 ,予纳洛酮治疗 ;对照组 132例 ,予一般治疗 ,观察神经功能缺损变化及血液流变学变化。结果　治疗组较对照组神经功能改善和血液流变学改变有显著性差异。结论　纳洛酮具有抗凝作用 ,对脑梗死患者神经功能恢复有较好疗效。     

爆裂性骨折所致眼球内陷的CT研究

目的:研究眼眶爆裂性骨折后,眼球内陷与眼眶容积扩大的关系并对眼球内陷进行早期预报。方法:28例单侧眼眶爆裂性骨折后1～350 d患者,分别测量双侧眼球位置和骨性眼眶容积值,计算患侧眼球内陷值(E)和骨性眼眶容积扩大值(V),应用pearson积矩法研究E、V相关性并建立直线回归方程。结果:28例患侧E、V呈正相关(r=0.88,P<0.001);15例≤24 d的患者直线回归方程为E=0.85 V-1.74(r=0.86,P<0.001),13例>24 d的患者直线回归方程为E=0.86 V-0.60(r=0.9,P<0.001)。结论:眼球内陷值与眼眶容积扩大值高度相关;1 mL眼眶容积的扩大,可引起大约0.9mm(0.85～0.86 mm)的眼球内陷。与伤后>24 d的相比,≤24 d的眼球有明显的抗拒内陷的趋势,>24 d之后,这种趋势逐渐消失,随之发生眼球内陷。     

指尖离断再植的血运重建

目的 探讨指尖离断再植时血运重建的方式。方法 临床上采用4种血运重建的万式对352例401指尖离断进行再植:①吻合指动脉与静脉的断指再植;②动-静脉转流方式的断指再植;③只吻合指动脉的断指再植;④静脉动脉化的断指再植。结果 352例401指,成活381指,成活率95％,手指外形和长度与健指相似,两点辨别觉2～6mm,指甲生长良好。结论 依据显微镜下清创所见离断指尖动静脉损伤状况,选用不同的血运重建方式,有助于扩大指尖再植适应证,提高再植成功率。     

转NGF基因雪旺细胞和胚胎脊髓细胞悬液移植治疗脊髓损伤的实验研究

目的：探讨胚胎脊髓细胞悬液（FSCS），雪旺细胞（SC）和神经生长因子（NGF）修复脊髓损伤的疗效。方法：用改良Allen法制成4组脊髓损伤动物模型（80只），1周后分别行空白对照组（DMEM），FSCS，FSCS＋SC和FSCS＋NGFSC移植入脊髓损伤部位，脊髓移植1个月和3个月后分别采用免疫组化染色法观察神经丝蛋白（NF），髓基质蛋白（MBP），5羟色胺（5－HT）的表达情况，并根据图像分析各实验组脊髓移植物的免疫阳性反应变化；通过改良的Tarlov评分方法观察行为变化。结果：FSCS＋NGFSC联合移植治疗脊髓损伤能够明显促进脊髓再生和修复，改善脊髓功能，4组疗效之间有显著性差异（P＜0．01），结论：转NGF基因雪旺细胞和胚胎脊髓细胞悬液移植治疗脊髓损伤时NGF基因修饰的SC局部释放的NGF能够刺激受损轴突再生，促进FSCS移植物与受损脊髓的整合，促进脊髓损伤的再生修复。     

经乳突颞下迷路外进路面神经高位减压术

目的 探讨颞骨外伤性骨折面瘫,保全和重建听骨链的面神经迷路段减压术对面瘫与听力恢复的效果。方法 对7例颞骨高位骨折引起面瘫者,行保全听骨链的经乳突颞下迷路外进路面神经高位减压术。结果 术后随访0.5～4.2年,面瘫恢复致H-BⅠ级3例,H-BⅡ级2例,H-BⅢ级2例。术中保全听骨链,术后语频区听力平均提高26dB。结论 颞骨高位外伤性骨折面瘫,行乳突颞下迷路外径路,进行面神经高位减压保全和重建听骨链效果满意。     

婴幼儿手术损伤与外周血淋巴细胞凋亡的关系

目的　手术应激可引起细胞介导的免疫受到抑制 ,包括淋巴细胞数量减少 ,导致感染并发症增加 ,确切的原因尚不清楚 ,本研究探讨婴幼儿大手术损伤和淋巴细胞凋亡的关系。方法　 1 2例择期大手术婴幼儿和 6例严重感染的婴幼儿 ,择期手术患儿包括先天性胆总管囊肿 7例和先天性巨结肠 5例 ,其中男 8例 ,女 4例 ,年龄 6个月～ 3岁 ;6例正常婴幼儿作为对照 ,抽取外周血 ,用Boyum描述的方法借助梯度离心分离淋巴细胞 ,用AnnexinV/PI双染色法来分析淋巴细胞早期凋亡情况 ,流式细胞仪测定淋巴细胞Fas的表达。结果　术后患儿外周血淋巴细胞明显下降 ,术后 1d为最低 ,术后 3d仍处于低值。大手术组患儿淋巴细胞凋亡率为 (1 4 .1± 1 .1 ) % ,严重感染组为 (1 2 .3±2 .0 ) % ,与正常对照组 (5 .1± 0 .3) %相比有统计学意义 (P <0 .0 5) ;Fas阳性淋巴细胞百分数术毕为(50 .3± 6 .3) % ,术后 1d为 (49.3± 4 .3) % ,与术前 (36 .3± 1 .1 % )相比有统计学意义 (P <0 .0 5)。结论　经历大手术的患儿循环淋巴细胞呈现凋亡的早期征象 ,可能是全身炎症反应中免疫细胞低反应的原因     

药物对体外冲击波碎石术致儿童急性肾损伤的保护作用

目的　探讨抗氧化维生素和钙通道阻滞剂对体外冲击波碎石术 (ESWL)所致儿童急性肾损伤的保护作用。方法　 2 6例肾盂内结石患儿 ,男 1 8例 ,女 8例 ;年龄 7～ 1 2岁 ,平均 9.8岁。右肾结石 1 1例 ,左肾结石 1 5例 ,结石直径 6～ 1 3mm ,平均 8.6mm。经腹部平片和B超确诊。血清肌酐、尿素氮值均在正常范围。常规静脉尿路造影检查 ,显示结石侧肾无积水或轻度积水 ,轻度肾积水者其远端尿路通畅无梗阻 ;对侧肾功能正常。 2 6例接受ESWL的儿童肾结石患者随机分为用药组和对照组 ,每组 1 3例。用药组在术前 3d口服维生素E、C和硝苯地平 ,对照组不用药物。观察术前 1d、后 1d、后 1周 2 4h尿内皮素 (ET 1 )、尿丙二醛 (MDA)和尿N 乙酰 β D氨基葡萄糖苷酶 (NAG)变化 ,同时测定肾内血管阻力指数 (RI)。结果　对照组术后 1dET 1 (44.84± 1 6 .2 4 )ng/L、MDA(3 .97± 1 .1 6)nmol/L、NAG(56 .42± 1 2 .34)u·g- 1 ·cr- 1 和RI(0 .70 2± 0 .0 38)比术前及用药组明显增高 (P <0 .0 1 ) ;术后 1周MDA、NAG及RI仍高于术前水平 (P <0 .0 1 )。用药组术后 1d ,ET 1、MDA和RI较术前无明显增高 (P >0 .0 5) ;NAG较术前增高 (P <0 .0 5) ,但 1周内恢复术前水平。结论　抗氧化维生素和钙通道阻滞剂能减轻ESWL的脂质过