中青年慢性酒精中毒的BAEP分析

目的:探讨脑干听觉诱发电位(BAEP)在慢性酒精中毒诊断中的意义。方法:对35例慢性酒精中毒患者做常规 BAEP 检查,并对其结果与饮酒史长短、饮酒量多少的关系进行分析。结果:35例患者中异常为32例(占91.43%),其异常主要表现为两侧Ⅲ波、Ⅴ波的峰潜伏时及Ⅰ—Ⅲ波、Ⅰ—Ⅴ波峰间潜伏时延迟。其中25.7%伴Ⅰ波延迟、40%伴Ⅴ/Ⅰ<1。结论:BAEP 检查有助于临床上对慢性酒精中毒的早期诊断。     

Analysis of the mechanism of change in amplitude of the receptor potential of pacinian corpuscles in Ca++-Deficient solution

The causes of the rise in amplitude of the receptor potential (RP) of Pacinian corpuscles in Ca⁺⁺-free solution were investigated by the external perfusion method. In Ca⁺⁺-free solution the amplitude of RP was shown to increase, but this increase was blocked by the addition of 10–20 mM tetraethylammonium to the solution. A temporary increase in the amplitude of RP was observed in solution with 0.2 mM 2,4-dinitrophenol. The sensitivity of the receptor membrane to mechanical stimuli was unchanged in Ca⁺⁺-free solution. It is suggested that there are no negative charges near the mechanically sensitive ionic channel of the receptor membrane of Pacinian corpuscles which could affect the state of the gating system of the mechanically sensitive channel.Laboratory of General Physiology of Reception, I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR, V. N. Chernigovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 12, pp. 643–645, December, 1979.     

川芎嗪对休克血浆所致乳头肌电生理效应的影响

目的探讨川芎嗪（Lig）对休克血浆（SP）所致豚鼠心室乳头肌电生理特性改变的干预作用。方法利用常规玻璃微电极细胞内记录技术，观察SP对豚鼠心室乳头肌动作电位的影响及不同剂量Lig的干预作用。结果（1）用含有SP的灌流液灌流标本时，豚鼠心室乳头肌细胞动作电位的幅值（APA）、超射值（OS）均显著升高（P〈0．05），复极50％、90％时间（APD50、APD90）及动作电位时程（APD）均明显延长（P〈0．05）；（2）Lig可剂量依赖性地降低SP引起的APA、OS升高，延长APD50、APD90及APD，此种干预作用以5．12mmol／L Lig最为明显。结论SP可导致正常豚鼠心室乳头肌电生理特性的改变，而Lig可剂量依赖性地干预此种效应。     

Synaptic actions of the ventral root afferents on cat hindlimb motoneurons

Postsynaptic potentials (PSPs) with long latencies were evoked in cat hindlimb motoneurons by stimulation of the distal stump of a cut ventral root. Measurements of their latency and the threshold in the responsible afferent fibers showed that they were produced mainly by the activity of the unmyelinated fibers in the ventral root that enter the spinal cord through the dorsal root. Patterns of PSPs evoked in flexor and extensor motoneurons by ventral root stimulation were similar to those observed in the flexion reflex.     

Monovalent cation conductance of the sustained inward current in rabbit sinoatrial node cells

 Under the whole cell clamp, superfusion of the rabbit sinoatrial node cells with a Na⁺-free solution suppressed the sustained inward current (I_st), and the L-type Ca²⁺ current (I_Ca,L) could be recorded on depolarization less negative than –40 mV from the holding potential of –80 mV. On the other hand, replacement of Ca²⁺ with Mg²⁺ in the external solution suppressed inward-going I_Ca,L and isolated I_st. Under this condition, I_st measured as a nicardipine-sensitive current showed an activation threshold between –60 and –70 mV. The conductance sequence of I_st for monovalent ions was determined as Na⁺ > Li⁺ >> K⁺ @ Cs⁺ by replacing the external Na⁺ with these alkali metal ions. The contribution of I_st to the diastolic depolarization is discussed. Received: 12 June 1996 / Received after revision: 31 July 1996 / Accepted: 7 August 1996     

The selective processing of briefly presented affective pictures: an ERP analysis

Recent event-related potential (ERP) studies revealed the selective processing of affective pictures. The present study explored whether the same phenomenon can be observed when pictures are presented only briefly. Toward this end, pleasant, neutral, and unpleasant pictures from the International Affective Pictures Series were presented for 120 ms while event related potentials were measured by dense sensor arrays. As observed for longer picture presentations, brief affective pictures were selectively processed. Specifically, pleasant and unpleasant pictures were associated with an early endogenous negative shift over temporo-occipital sensors compared to neutral images. In addition, affective pictures elicited enlarged late positive potentials over centro-parietal sensor sites relative to neutral images. These data suggest that a quick glimpse of emotionally relevant stimuli appears sufficient to tune the brain for selective perceptual processing.     

Effect of an increased calcium ion concentration on electrical and contractile activity of the smooth muscles of the guinea pig ureter

Smooth muscle cells of the guinea pig ureter were studied by the double sucrose gap method. An increase in the calcium ion concentration in the Ringer-Locke solution to 22 mM led to hyperpolarization and to a slight increase in the resistance of the membrane. The amplitude of the first spike potential and the height of the plateau were lowered but the amplitude of the oscillations was increased. In sodium-free Ringer-Locke solution, when the action potential in the smooth muscle cells of the ureter was converted into a simple spike potential, a marked increase in amplitude of the action potential was observed with an increase in the calcium ion concentration.Department of Neuromuscular Physiology, A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Gorev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 5, pp. 522–526, May, 1977.     

管花苷B对抗H2O2诱导的PC12细胞凋亡

目的：观察肉苁蓉提取物管花苷B对H₂O₂诱导的PC12细胞损伤的影响。方法：用MTT法检测细胞存活率，以激光共聚焦显微镜荧光染色法检测细胞内活性氧的产生和线粒体膜电位的变化，DNA琼脂糖凝胶电泳和流式细胞仪检测细胞凋亡的发生，并用荧光酶标仪测定caspase-3的活性。结果：100 μmol·L^-1 H₂O₂处理细胞24 h显著降低细胞的存活率；诱导细胞发生凋亡，凋亡率达48.0％；细胞内活性氧水平及caspase-3的活性显著升高；而线粒体膜电位却明显降低，红/绿荧光强度的比值由正常的5.97降低为0.41左右。而预先给予1、10或100 mg·L^-1浓度的管花苷B处理细胞12 h，可显著提高细胞存活率；并可有效抑制DNA ladder的发生；流式细胞仪检测凋亡率分别降低到30.9%、18.3%和6.2%；激光共聚焦显微镜结果显示管花苷B可明显降低细胞内活性氧的水平；并可逐渐恢复线粒体的高能量状态；caspase-3的活性不断降低，并呈现了一定的剂量依赖性。结论：管花苷B能显著地抑制H₂O₂诱导的PC12细胞凋亡，其神经细胞保护作用可能与其降低细胞内活性氧水平，维持线粒体膜电位的高能状态和抑制caspase-3的活性有关。     

帕金森病患者诱发电位研究

目的 :研究帕金森病 (PD)患者脑干听觉诱发电位 (BAEP)和视觉诱发电位 (VEP)的变化及其与临床症状的关系。方法 :检测 70例PD患者BAEP和VEP ,并设正常对照组 6 0例作对照。结果 :PD组BAEP异常 31例 (44 % ) ,正常对照组异常 11例 (18% ) ,P <0 0 1。VEPN75、P10 0、N135的潜伏期分别为 93 2± 15 1ms、12 5 2± 12 .4ms和 15 7 2± 19 5ms ,均较正常对照组 83 1± 14 8ms、10 4 2± 7 3ms和139 4± 14 4ms明显延长 ,P <0 0 1;PD患者VEP的P10 0潜伏期与UPDRS评分呈正相关 ,r =0 6 1,P <0 0 1。结论 :BAEP和VEP可客观地反映PD患者听觉和视觉通路电生理的变化。