Apparent rapid tolerance to ethanol for nerve conduction velocity

Apparent rapid tolerance to ethanol for decrease in nerve conduction velocity, lasting up to one day but to seven days, was shown in HS mice following a single injection (i.p.) of 3.0 g EtOH/kg body wt. Relative conduction time (RCT-reciprocal of velocity) was studied in the caudal nerves of 60 mice. In Exp. 1 30 mice were tested twice, 7 days apart; these showed no significant change in RCT on re-test. In Exp. 2 30 mice tested twice, 1 day apart, showed a significantly smaller response to ethanol in the second test. This result suggests that ethanol tolerance in peripheral nerve conduction velocity may develop in these mice after a single ethanol dose. In addition, ethanol effects on two measures of CNS depression also suggest tolerance after one day and lasting to seven days. The basis for these apparent examples of tolerance to ethanol is not clear.     

Demonstration of mucous mechanoreceptors in the lower esophageal sphincter. Comparison with muscle mechanoreceptors

In anaesthetized cats, vagal unitary discharges originating from the Lower Oesophageal Sphincter (L.O.S.) were recorded in nodose ganglia by means of glass microelectrodes. Numerous mechanoreceptors located both in mucosa and muscular layers were found in L.O.S. The mucus mechanoreceptors (high threshold receptors) were activated by strong compressions and distensions, by rapid passage of liquid through the oesophagus and by striking the mucosa. The muscular mechanoreceptors (low threshold receptors) responded to contraction and distension of L.O.S. Both receptors were connected to nonmyelinated fibres (conduction velocity: 0.9-1.4 m/sec).     

Diabetic polyneuropathy. 3. Electroneurographic findings in diabetics and their relationships to age and duration of diabetes

Nerve conduction velocities were determined in patients with diabetes mellitus: motor conduction of the median nerve in 778 patients, sensory conduction of the median nerve in 680 patients and motor conduction of the tibial nerve in 745 patients. In 40.9% out of 778 patients at least one of the three nerve conduction velocities were found within pathological ranges. 30.4% of 227 patients below 19 years of age in whom the duration of the disease did not exceed four years exhibited at least one delayed nerve conduction velocity. Clinical signs of polyneuropathy in children and in adolescents below 19 years of age are rare (0.6%). In contrast delayed nerve conduction velocities were found in 29.4%. Metabolic disturbance of peripheral nerve function is assumed to be responsible in these patients, for angiopathy in children and adolescents is very rare too.     

Sorbitol, inositol and nerve conduction in diabetes

Motor nerve conduction velocity was lower in streptozotocin-diabetic rats than in controls. Treatment with the aldose reductase inhibitor Sorbinil restored conduction velocity to normal. Diabetic rats had an increased concentration of sorbitol and reduced free inositol in sciatic nerve. Sorbinil corrected both defects. Inositol administration to diabetic rats also restored conduction velocity to normal. Genetically diabetic mice had reduced concentrations of inositol in sciatic nerve but fructose and sorbitol were normal. Glucose concentration was considerably increased.     

神经传导测定技术对腕管综合征病情评估的价值

目的:近年来腕管综合征发病率逐年升高,然而其慢性、隐匿性不易引起人们的重视,发现时往往已造成较大的危害。本文探讨腕管综合征的神经传导测定对病情评估的临床价值,旨在为患者腕管综合征早期发现和后续治疗提供进一步的临床参考依据。方法:选取我院124例确诊的腕管综合征患者。其中无大鱼际肌萎缩者有64例,并选取平均年龄相近的64例正常人作为对照(组A);有大鱼际肌畏缩者60例,并选取平均年龄相近的60例正常人作为对照(组B)。A、B组均经行神经电图检查,握力测定和两点辨别觉测定,分析神经传导速度改变与感觉、运动功能减退程度的关系。结果:A、B两组患者均有不同程度的神经传导改变:在A组患者神经传导改变中,运动和感觉传导速度(MCV和SCV)轻度下降,运动和感觉电位波幅(CMAP和SNAP)轻度下降,潜伏期(ML)轻度延长;在B组患者神经传导中,运动和感觉传导速度(MCV和SCV)明显下降,运动和感觉电位波幅(CMAP和SNAP)明显下降,潜伏期明显延长。结论:腕管综合征患者不同的临床表现有不同程度的神经电图表现,因此神经电图对神经传导的测定结果对腕管综合征患者的病情有良好的评估价值,值得临床推广。     

补阳还五汤联合针灸对糖尿病周围神经病变患者血糖代谢、神经传导速度和血液流变学的影响

摘要 目的：探讨补阳还五汤联合针灸对糖尿病周围神经病变（DPN）患者血糖代谢、神经传导速度和血液流变学的影响。方法：选取我院2018年4月-2021年4月期间收治的100例DPN患者,按照双色球法将患者分为对照组（50例,常规西医治疗）和研究组（50例,对照组基础上接受补阳还五汤联合针灸治疗）。均治疗4周,对比两组临床疗效、血糖代谢水平、神经传导速度和血液流变学。结果：治疗后研究组临床总有效率（94.00%）,高于对照组（72.00%）（P<0.05）。治疗后研究组的空腹血糖（FPG）、餐后2 h血糖（2hPG）、糖化血红蛋白（HbA1c）水平均低于对照组（P<0.05）。治疗后研究组的腓总神经和正中神经感觉神经传导速度（SNCV）、运动神经传导速度（MNCV）均较对照组高（P<0.05）。治疗后研究组的红细胞比积、纤维蛋白原、全血粘度（高切）及全血粘度（低切）水平均低于对照组（P<0.05）。结论：补阳还五汤联合针灸治疗DPN患者疗效显著,有效提高其神经传导速度,改善其血糖代谢和血液流变学。     

The diabetic polyneuropathy. I. Relation between impaired function in peripheral nerves and clinical findings

789 patients with diabetes mellitus were studied by clinical and electroneurographical investigation. Motor and sensory conduction velocities of the median nerve and motor conduction velocity of the tibial nerve were determined. 86.1% of the patients suffered from juvenile diabetes, and 13.9% from maturity onset diabetes. Average duration of the disease was 9.5 years, average age of the patients was 26.7 years. Clinical signs of polyneuropathy were found in 19.1%. In 40.9% of the patients at least one of 3 conduction velocities was found to be delayed. Patients with clinical signs of polyneuropathy exhibited delayed nerve conduction velocities and delayed distal latencies. Diagnosis of polyneuropathy almost with certainty is possible by determining the three nerve conduction velocities and the three corresponding distal latencies. 22% of patients without clinical signs of polyneuropathy exhibited electroneurographical signs of impaired peripheral nerve function. Heredity, body weight, lipid metabolism, actual metabolic balance, and treatment were found to be without any significant influence on nerve conduction velocity.     

低频脉冲刺激穴位疗法联合规律有氧运动对2型糖尿病周围神经病变患者感觉阈值、神经传导速度和血液流变学的影响

摘要 目的：探讨低频脉冲刺激穴位疗法联合规律有氧运动对2型糖尿病周围神经病变（DPN）患者感觉阈值、神经传导速度和血液流变学的影响。方法：选取2020年1月~2022年1月期间贵州中医药大学第二附属医院收治的DPN患者136例。根据随机数字表法分为对照组（n=68,常规治疗联合规律有氧运动）和研究组（n=68,对照组基础上接受低频脉冲刺激穴位疗法）,两组以14 d为1个疗程,均治疗2个疗程。对比两组疗效、感觉阈值、神经传导速度和血液流变学变化。结果：研究组的临床总有效率91.18%（62/68）高于对照组75%（51/68）（P<0.05）。两组治疗2个疗程后腓总神经感觉神经传导速度（SCV）、胫神经SCV、腓总神经运动神经传导速度（MCV）、胫神经MCV均升高,且研究组的变化程度大于对照组（P<0.05）。两组治疗2个疗程后全血黏度值(高切、低切)、红细胞压积、血浆黏度、血小板黏附率均下降,且研究组的变化程度大于对照组（P<0.05）。两组治疗2个疗程后神经症状积分、神经反射、感觉功能和总分均下降,且研究组的变化程度大于对照组（P<0.05）。结论：低频脉冲刺激穴位疗法联合规律有氧运动治疗DPN患者,可提高神经传导速度,改善感觉阈值和血液流变学。     

Field hockey players have different values of ulnar and tibial motor nerve conduction velocity than soccer and tennis players

The aim of this study was to describe motor nerve conduction velocity in upper and lower extremities in sportsmen. Fifteen high-level field hockey players, seventeen soccer players and ten tennis players were recruited from the Polish National Field Hockey League, Polish Soccer League Clubs, and Polish Tennis Association clubs,respectively. The control group comprised of seventeen healthy, non-active young men. Nerve conduction velocities of ulnar and tibial nerve were assessed with NeuroScreen electromyograph (Toennies, Germany) equipped with standard techniques of supramaximal percutaneus stimulation with constant current and surface electrodes. No significant differences in motor nerve conduction velocities were found between dominant and non-dominant limbs in each studied group. Ulnar nerve conduction velocity measured from above elbow to below elbow was significantly lower only in the field hockey players' dominant limb. Tibial conduction velocity of the field hockey players' non-dominant lower limb was higher in comparison to the tennis players and the control group. There was no significant correlation between body mass and NCV as well as between height of subjects and NCV in both athletes or non-athletes. A slight trend towards a lower TCV values in athletes with longer duration of practicing sport was found. It was most pronounced in the non-dominant lower extremity of field hockey players.     

Rate of excitation propagation in a reduced Hodgkins-Huxley model. II. Slow relaxation of the sodium current]

The influence of sodium current activation on the value of nerve excitation conduction velocity is investigated on the basis of Hodgkin-Huxley model. The potassium activation and sodium inactivation are considered as slow processes which do not develop to an appreciable extent in the region of conduction velocity formation. The system of equations was derived and solved analytically after neglecting the dependency of sodium relaxation time on potential; the approximation of steady-state sodium activation was also used with the help of Hevyside function. The algebraic equation for conduction velocity was obtained; its solution has a simple analytical form in two limits of rapid and slow sodium current relaxation. The comparison with the experimental data has shown that at not very high temperatures the slow (compared to the potential dynamics) sodium current relaxation approximation is more appropriate. The dependency of impulse velocity on capacitance and conductance of the fiber was analyzed.     

Prostaglandin E1 modifies nerve conduction and interferes with local anaesthetic action

Prostaglandin E1 (PGE1) altered both the amplitude and conduction velocity of the compound action potential in frog sciatic nerve. Concentrations up to 1 ng/ml increased both amplitude and conduction velocity but at higher concentrations both effects were reversed. Procaine, chloroquine, indomethacin and SC19220 all reduced action potential amplitude and conduction velocity. These local anaesthetic type actions could be partially or completely prevented by PGE1.     

Neural conduction velocity of the human auditory nerve: bipolar recordings from the exposed intracranial portion of the eighth nerve during vestibular nerve section

We measured the conduction velocity of the intracranial portion of the auditory nerve in 3 patients undergoing vestibular nerve section to treat Ménière's disease. The conduction velocity varied from patient to patient, with an average value of 15.1 m/sec. The latency of peak III of the brain-stem auditory evoked potentials (BAEPs) increased by an average of 0.5 msec as a result of exposure of the eighth nerve, and if that increase is assumed to affect the entire length of the auditory nerve (2.6 cm) evenly, then the corrected estimate of conduction velocity would be 22.0 m/sec. Estimates of conduction velocity based on the interpeak latencies of peaks I and II of the BAEP, assuming that peak II is generated by the mid-portion of the intracranial segment of the auditory nerve, yielded similar values of conduction velocities (about 20 m/sec).     

Prostaglandin E1 modifies nerve conduction and interferes with local anaesthetic action.

Prostaglandin E1 (PGE1) altered both the amplitude and conduction velocity of the compound action potential in frog sciatic nerve. Concentrations up to 1 ng/ml increased both amplitude and conduction velocity but at higher concentrations both effects were reversed. Procaine, chloroquine, indomethacin and SC19220 all reduced action potential amplitude and conduction velocity. These local anaesthetic type actions could be partially or completely prevented by PGE1.     

TOCP对鸡迷走神经不同纤维成份传导速度和兴奋性的影响

对磷酸三邻甲苯醋(TOCP)染毒母鸡进行迷走神经不同纤维成份传导速度和兴奋性测定,发现实验组动物在染毒后14天迷走神经第5波(类似于C纤维)传导速度减慢30%,染毒后21天时减慢52%,并出现迷走神经各波兴奋性显著降低.实验结果说明,TOCP所致迟发性神经病可损害与内脏活动有关的迷走神经.     

Effect of vitamin C and E supplementation in modulating the peripheral nerve conduction following cold exposure in humans

Exposure to an extremely cold environment without proper protection leading to hypothermia is an emergency, one of the several complications of which is impairment in nerve conduction. Our previous work in the rat model has shown the beneficial effect of vitamin C in modulating the effect of hypothermia on nerve conduction. The present study aimed to evaluate the effect of vitamins C and E, administered alone or in combination, in modulating the effect of mild hypothermia on human ulnar nerve conduction. The study was carried out on 26 volunteers divided into three groups: group I received vitamin C supplementation (2000 mg/day in a single dose and 1,000 mg/day for the next 6 days), group II received vitamins C and E in combination (1,000 mg and 800 mg respectively in a single dose and 500 mg and 400 mg respectively for the next 6 days) and group III received vitamin E (800 mg in a single dose and the same for the next 6 days). The recordings were carried out before and after single and weekly supplementation in each group. There was a fall in ulnar nerve conduction velocity with a reduction in the oral temperature of 2–2.5 °C. Vitamin C administered alone and in combination with vitamin E reduced the fall in ulnar nerve conduction velocity. Prior supplementation with vitamin C and E could help ameliorate the impairment in human ulnar nerve conduction due to hypothermia.     

The diabetic polyneuropathy. II. Polyneuropathy, angiopathy and nerve conduction velocity

789 patients with diabetes mellitus were studied by clinical and electroneurographical examination. Motor conduction velocity of the median and the tibial nerve and sensory conduction of the median nerve were determined. 81.1% of the patients we suffering from diabetes which began in childhood or adolescence, 13.9% were suffering from maturity onset diabetes. Average duration of the disease was 9.5 years, average age was 26.7 years. Clinical signs of polyneuropathy were found in 19.1%. Typical findings were pain and paraesthesia, lack or abolition of triceps surae reflexes, impaired pallaesthesia on lower extremities. 48.3% of 151 patients with clinical signs of polyneuropathy were suffering from combined angiopathy, 32.5% from microangiopathy, 7.9% from macroangiopathy. Severity of complicating retinopathy and macroangio,athy were found to be correlated with polyneuropathy. 58.2% of 323 diabetics with at least one delayed nerve conduction velocity exhibited signs of angiopathy. In nearly 30% of children and adolescents after comparatively short duration of the disease at least one conduction velocity was delayed. In diabetic children and adolescents metabolic disturbances are assumed to cause peripheral nerve dysfunction.     

The “Lillie Transition”: models of the onset of saltatory conduction in myelinating axons

Almost 90 years ago, Lillie reported that rapid saltatory conduction arose in an iron wire model of nerve impulse propagation when he covered the wire with insulating sections of glass tubing equivalent to myelinated internodes. This led to his suggestion of a similar mechanism explaining rapid conduction in myelinated nerve. In both their evolution and their development, myelinating axons must make a similar transition between continuous and saltatory conduction. Achieving a smooth transition is a potential challenge that we examined in computer models simulating a segmented insulating sheath surrounding an axon having Hodgkin-Huxley squid parameters. With a wide gap under the sheath, conduction was continuous. As the gap was reduced, conduction initially slowed, owing to the increased extra-axonal resistance, then increased (the “rise”) up to several times that of the unmyelinated fiber, as saltatory conduction set in. The conduction velocity slowdown was little affected by the number of myelin layers or modest changes in the size of the “node,” but strongly affected by the size of the “internode” and axon diameter. The steepness of the rise of rapid conduction was greatly affected by the number of myelin layers and axon diameter, variably affected by internode length and little affected by node length. The transition to saltatory conduction occurred at surprisingly wide gaps and the improvement in conduction speed persisted to surprisingly small gaps. The study demonstrates that the specialized paranodal seals between myelin and axon, and indeed even the clustering of sodium channels at the nodes, are not necessary for saltatory conduction.     

Effect of Treating Streptozotocin-Induced Diabetic Rats With Sorbinil,Myo-Inositol or Aminoguanidine on Endoneurial Blood Flow,Motor Nerve Conduction Velocity and Vascular Function of Epineurial Arterioles of the Sciatic Nerve

Previously we have demonstrated that diabetes causes impairment in vascular function of epineurial vessels, which precedes the slowing of motor nerve conduction velocity. Treatment of diabetic rats with aldose reductase inhibitors, aminoguanidine or myo-inositol supplementation have been shown to improve motor nerve conduction velocity and/or decreased endoneurial blood flow. However, the effect these treatments have on vascular reactivity of epineurial vessels of the sciatic nerve is unknown. In these studies we examined the effect of treating streptozotocininduced rats with sorbinil, aminoguanidine or myo-inositol on motor nerve conduction velocity, endoneurial blood flow and endothelium dependent vascular relaxation of arterioles that provide circulation to the region of the sciatic nerve. Treating diabetic rats with sorbinil, aminoguanidine or myo-inositol improved the reduction of endoneurial blood flow and motor nerve conduction velocity. However, only sorbinil treatment significantly improved the diabetes-induced impairment of acetylcholinemediated vasodilation of epineurial vessels of the sciatic nerve. All three treatments were efficacious in preventing the appropriate metabolic derangements associated with either activation of the polyol pathway or increased nonenzymatic glycation. In addition, sorbinil was shown to prevent the diabetes-induced decrease in lens glutathione level. However, other markers of oxidative stress were not vividly improved by these treatments. These studies suggest that sorbinil treatment may be more effective in preventing neural dysfunction in diabetes than either aminoguanidine or myoinositol.     

木丹颗粒联合羟苯磺酸钙胶囊对糖尿病周围神经病变患者神经传导速度、血液流变学和氧化应激的影响

摘要 目的：探讨木丹颗粒联合羟苯磺酸钙胶囊对糖尿病周围神经病变（DPN）患者神经传导速度、血液流变学和氧化应激的影响。方法：选取2018年9月~2020年8月期间我院收治的120例DPN患者。按照随机数字表法分为观察组（60例,木丹颗粒联合羟苯磺酸钙胶囊治疗）和对照组（60例,羟苯磺酸钙胶囊治疗）,均治疗8周。对比两组疗效、神经传导速度、血液流变学和氧化应激,记录两组不良反应发生情况。结果：观察组的临床总有效率高于对照组（P<0.05）。观察组治疗后正中神经、腓总神经的运动传导速度（MNCV）和感觉传导速度（SNCV）均较治疗前升高,且高于对照组（P<0.05）。两组治疗后全血低切黏度、全血高切黏度、纤维蛋白原、血浆黏度均较治疗前降低,且观察组低于对照组（P<0.05）。两组治疗后丙二醛（MDA）较治疗前降低,超氧化物歧化酶（SOD）较治疗前升高（P<0.05）,且观察组MDA较对照组低,SOD较对照组高（P<0.05）。两组不良反应发生率对比无明显差异（P>0.05）。结论：木丹颗粒联合羟苯磺酸钙胶囊治疗DPN患者疗效确切,可提高患者神经传导速度和抗氧化应激能力,改善血液流变学状态,安全可靠。     

Ganglioside treatment of diabetic rats; effects on nerve adenosine triphosphatase activity and motor nerve conduction velocity

Ouabain-sensitive ATPase activity (expressed as nmol ADP produced/h/mg (wet) nerve +/- SEM) was measured in homogenates of sciatic nerve from control rats and rats with streptozotocin-induced diabetes of 8 wk duration. Nerves from diabetic rats showed activity (21.7 +/- 2.0) which was significantly (p less than 0.05) less than that of controls (34.6 +/- 4.8). These animals also showed a deficit in conduction velocity (m/sec +/- SEM) of sciatic nerve motoneurones (50.7 +/- 0.4 vs. 57.7 +/- 0.7 in controls; p less than 0.001). In parallel, matched control and diabetic groups were treated daily with mixed gangliosides extracted from bovine brain (10 mg/kg i.p.). After such treatment for 8 wk the deficit in ouabain-sensitive ATPase activity did not develop in the diabetic group (treated diabetics, 31.9 +/- 3.7; treated controls, 34.5 +/- 3.8). However, the treatment did not affect the deficit in motor nerve conduction velocity (treated diabetics, 50.9 +/- 1.1 vs. treated controls, 57.9 +/- 0.5; p less than 0.001). Accumulations of the polyol pathway metabolites--sorbitol and fructose--together with depletion of nerve myo-inositol were similar in both diabetic groups. These data indicate an etiology for the conduction velocity deficit which differs from that of the deficit in ouabain-sensitive ATPase.