Vagus nerve stimulation in cerebral stroke:biological mechanisms,therapeutic modalities,clinical applications,and future directions

Stroke is a major disorder of the central nervous system that poses a serious threat to human life and quality of life.Many stro ke victims are left with long-term neurological dysfunction,which adversely affects the well-being of the individual and the broader socioeconomic impact.Currently,poststroke brain dysfunction is a major and difficult area of treatment.Vagus nerve stimulation is a Food and Drug Administration-approved exploratory treatment option for autis m,refractory depression,epilepsy,and Alzheimer’s disease.It is expected to be a novel therapeutic technique for the treatment of stroke owing to its association with multiple mechanisms such as alte ring neurotransmitters and the plasticity of central neuro ns.In animal models of acute ischemic stroke,vagus nerve stimulation has been shown to reduce infarct size,reduce post-stroke neurological damage,and improve learning and memory capacity in rats with stroke by reducing the inflammatory response,regulating bloodbrain barrier permeability,and promoting angiogenesis and neurogenesis.At present,vagus nerve stimulation includes both invasive and non-invasive vagus nerve stimulation.Clinical studies have found that invasive vagus nerve stimulation combined with rehabilitation therapy is effective in im proving upper limb motor and cognitive abilities in stroke patients.Further clinical studies have shown that non-invasive vagus nerve stimulation,including ear/ce rvical vagus nerve stimulation,can stimulate vagal projections to the central nervous system similarly to invasive vagus nerve stimulation and can have the same effect.In this paper,we first describe the multiple effects of vagus nerve stimulation in stroke,and then discuss in depth its neuroprotective mechanisms in ischemic stroke.We go on to outline the res ults of the current major clinical applications of invasive and non-invasive vagus nerve stimulation.Finally,we provide a more comprehensive evaluation of the advantages and disadvantages of different types of vagus nerve stimulation in the treatment of cerebral ischemia and provide an outlook on the developmental trends.We believe that vagus nerve stimulation,as an effective treatment for stroke,will be widely used in clinical practice to promote the recovery of stroke patients and reduce the incidence of disability.

Preliminary analysis of the effect of vagus nerve stimulation in the treatment of children with intractable epilepsy

BACKGROUND Implant vagus nerve stimulation is an adjunctive treatment for intractable epilepsy when patients are not suitable for resective surgery.AIM To identify the safety and efficacy of vagus nerve stimulation in children with intractable epilepsy and analyze the effects on different epilepsy syndromes.METHODS Eligible children with intractable epilepsy were admitted to the study.We collected data from preoperative assessments as the baseline.During the followup time,we recorded the process of seizures(frequency,duration,and seizure type),the changes of drugs or parameters,the complications,etc.The mean reduction rate of seizures,response rate,and McHugh scale were chosen as the outcomes.RESULTS A total of 213 patients were implanted with Tsinghua Pins vagus nerve stimulators,and the average age was 6.6 years.In the follow-up time of postoperative 3 mo,6 mo,12 mo,18 mo,and 24 mo,the average reduction rate was 30.2%,49.5%,56.3%,59.4%,and 63.2%,while the response rate was 21.8%,62.5%,57.1%,69.2%,and 70.7%.In addition,implanted vagus nerve stimulation had different effects on epilepsy syndromes.The reduction rate of West syndrome increased from 36.4%(postoperative 6 m)to 74.3%(postoperative 24 m).The reduction rate of Lennox-Gastaut syndrome improved from 25.4%to 73.1%in 24 mo.The chi-square test of the five efficacy grades showed P<0.05.The comparison between the 3-mo follow-up and the 6-mo follow-up showed P<0.05,and the comparison between the 6-mo follow-up and the 24-mo follow-up showed P>0.05.CONCLUSION Vagus nerve stimulation is safe and effective in children with intractable epilepsy,and the seizure reduction occurred in a time-dependent manner.Moreover,patients with West syndrome may get the most benefits.

Pathogenesis, diagnosis, and treatment of epilepsy: electromagnetic stimulation-mediated neuromodulation therapy and new technologies

Epilepsy is a severe,relapsing,and multifactorial neurological disorder.Studies regarding the accurate diagnosis,prognosis,and in-depth pathogenesis are crucial for the precise and effective treatment of epilepsy.The pathogenesis of epilepsy is complex and involves alterations in variables such as gene expression,protein expression,ion channel activity,energy metabolites,and gut microbiota composition.Satisfactory results are lacking for conventional treatments for epilepsy.Surgical resection of lesions,drug therapy,and non-drug interventions are mainly used in clinical practice to treat pain associated with epilepsy.Non-pharmacological treatments,such as a ketogenic diet,gene therapy for nerve regeneration,and neural regulation,are currently areas of research focus.This review provides a comprehensive overview of the pathogenesis,diagnostic methods,and treatments of epilepsy.It also elaborates on the theoretical basis,treatment modes,and effects of invasive nerve stimulation in neurotherapy,including percutaneous vagus nerve stimulation,deep brain electrical stimulation,repetitive nerve electrical stimulation,in addition to non-invasive transcranial magnetic stimulation and transcranial direct current stimulation.Numerous studies have shown that electromagnetic stimulation-mediated neuromodulation therapy can markedly improve neurological function and reduce the frequency of epileptic seizures.Additionally,many new technologies for the diagnosis and treatment of epilepsy are being explored.However,current research is mainly focused on analyzing patients’clinical manifestations and exploring relevant diagnostic and treatment methods to study the pathogenesis at a molecular level,which has led to a lack of consensus regarding the mechanisms related to the disease.

The role of axon guidance molecules in the pathogenesis of epilepsy

Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target novel cellular and molecular mechanisms and mechanisms of action. Increasing evidence suggests that axon guidance molecules play a role in the structural and functional modifications of neural networks and that the dysregulation of these molecules is associated with epilepsy susceptibility. In this review, we discuss the essential role of axon guidance molecules in neuronal activity in patients with epilepsy as well as the impact of these molecules on synaptic plasticity and brain tissue remodeling. Furthermore, we examine the relationship between axon guidance molecules and neuroinflammation, as well as the structural changes in specific brain regions that contribute to the development of epilepsy. Ample evidence indicates that axon guidance molecules, including semaphorins and ephrins, play a fundamental role in guiding axon growth and the establishment of synaptic connections. Deviations in their expression or function can disrupt neuronal connections, ultimately leading to epileptic seizures. The remodeling of neural networks is a significant characteristic of epilepsy, with axon guidance molecules playing a role in the dynamic reorganization of neural circuits. This, in turn, affects synapse formation and elimination. Dysregulation of these molecules can upset the delicate balance between excitation and inhibition within a neural network, thereby increasing the risk of overexcitation and the development of epilepsy. Inflammatory signals can regulate the expression and function of axon guidance molecules, thus influencing axonal growth, axon orientation, and synaptic plasticity. The dysregulation of neuroinflammation can intensify neuronal dysfunction and contribute to the occurrence of epilepsy. This review delves into the mechanisms associated with the pathogenicity of axon guidance molecules in epilepsy, offering a valuable reference for the exploration of therapeutic targets and presenting a fresh perspective on treatment strategies for this condition.

Transcutaneous auricular vagus nerve stimulation for functional gastrointestinal disorders:From understanding to application

Functional gastrointestinal disorders(FGIDs)are debilitating diseases of the digestive system that severely impair an individual’s qualityof life and impose a significant economic burden.However,themechanisms underlying the pathogenesis of FGIDs and effective treatment options remain unclear.Transcutaneous auricular vagus nerve stimulation(taVNS),a novel neuromodulation therapy,has shown promising therapeutic outcomes in the treatment of FGIDs.This study conducted a comprehensive analysis of the development of taVNS and its relationshipwith vagus nerve stimulation and explored the clinical application of taVNS inmanaging FGIDs,including functional dyspepsia,irritable bowel syndrome,and functional constipation.Additionally,this study investigated the pathophysiological mechanisms of taVNS in FGIDs and reviewed its application as a holistic treatment approach,aiming to provide new insights into its therapeutic potential.

Young children with multidrug-resistant epilepsy and vagus nerve stimulation responding to perampanel: A case report

BACKGROUND Perampanel(PER),a third-generation antiepileptic drug,is a selective and noncompetitiveα-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist,and has been approved for the treatment of adults and adolescents with focal epilepsy.However,there are only a few studies about the efficacy and tolerability of PER in young children with multidrug-resistant epilepsy.In this case,we aimed to share our clinical experience in this group.CASE SUMMARY A 4-year-old boy without perinatal asphyxia and familial history of epilepsy began to have ictal seizures from age 14 mo,with jerky movement of four limbs and head nodding.Abnormal multifocal discharge and background activity were recorded through electroencephalography,and no pathogenic mutation was found in the whole exome sequencing for the patient and his parents.He had received valproate,levetiracetam,topiramate,oxcarbazepine,clonazepam and lacosamide sequentially at different times,but he still had frequent seizures even after vagus nerve stimulation(VNS)implantation.He was diagnosed with idiopathic multidrug-resistant epilepsy.However,his seizure frequency was significantly reduced after PER administration in a dose-dependent manner,and better cognitive behavior was observed.In addition,the adverse reactions of anger and aggression also appeared.CONCLUSION PER is effective as add-on therapy for young children with multidrug-resistant epilepsy who have previously undergone VNS implantation.

Interleukin-6 in epilepsy and its neuropsychiatric comorbidities: How to bridge the gap

There is growing evidence that interleukin(IL)-6 plays an important role in neurological and psychiatric disorders.This editorial comments on the study published in the recent issue of the World Journal of Psychiatry,which employed Mendelian randomization to identify a causal relationship between IL-6 receptor blockade and decreased epilepsy incidence.The purpose of this editorial is to highlight the dual effects of IL-6 in epilepsy and its related neuropsychiatric comorbidities.IL-6 plays a critical role in the facilitation of epileptogenesis and maintenance of epileptic seizures and is implicated in neuroinflammatory proce-sses associated with epilepsy.Furthermore,IL-6 significantly influences mood regulation and cognitive dysfunction in patients with epilepsy,highlighting its involvement in neuropsychiatric comorbidities.In summary,IL-6 is not only a pivotal factor in the pathogenesis of epilepsy but also significantly contributes to the emergence of epilepsy-related neuropsychiatric complications.Future resear-ch should prioritize elucidating the specific mechanisms by which IL-6 operates across different subtypes,stages and neuropsychiatric comorbidities of epilepsy,with the aim of developing more precise and effective interventions.Furthermore,the potential of IL-6 as a biomarker for the early diagnosis and prognosis of epile-psy warrants further investigation.

Therapeutic potential of Carum carvi in depression,memory loss,and hippocampal sclerosis reversal in temporal lobe epilepsy

Background:Epilepsy is a disease characterized by unprovoked seizures,and it affects around 70 million people worldwide.Standard treatment is ineffective in one third of all epilepsy patients.Temporal Lobe Epilepsy with Hippocampal Sclerosis(TLE-HS)is the most drug-resistant form of epilepsy,and it also impacts physical,mental,and psychological well-being of patients.Carum carvi extract has demonstrated anti-convulsant,anti-depressant,and anxiolytic properties.This study was designed to investigate if Carum carvi extract can alleviate depression and memory loss symptoms in a TLE-HS animal model.Methods:Male Sprague Dawley rats were used to create a model of TLE-HS and Carum carvi extract treatment,along with appropriate controls,was used to test the efficacy of this herbal extract in reducing the symptoms of depression and memory loss.Results:Forced swim test showed that Carum carvi extract treated TLE-HS rats resulted in significant improvement of the symptoms of depression.However,novel object recognition test showed that memory improvement did not occur.Conclusion:Depression significantly impacts the quality of life in TLE-HS patients,and this study has shown that Carum carvi extract should be explored further as an adjuvant treatment for TLE-HS patients to improve their quality of life.

Sodium channel mutation SCN1A T875M,D188V and associated dysfunction with drug resistant epilepsy

BACKGROUND The NaV1.1 sodium channel alpha subunit,encoded by SCN1A,is crucial for initiating and propagating action potentials in neurons.SCN1A gene has long been an established target in the etiology and therapy of epilepsy.However,very few studies have investigated the relevance of genetic variations in epilepsy and anti-epileptic drug resistance.AIM To investigate associations between polymorphisms,rs121917953 T/A and rs121918623 C/T,and drug resistance in epilepsy patients in the north Indian population.METHODS A total of 100 age-and sex-matched epilepsy patients(50 drug responsive and 50 drug resistant subjects)were recruited and SCN1A rs121918623 C/T*and rs121917953 T/A*polymorphisms were analyzed by the allele specific-PCR technique.χ^(2)and Fisher’s exact test were used to estimate differences between the distribution of SCN1A rs121918623 and rs121917953 gene polymorphisms among various groups.The association between distinct rs121917953 genotypes and drug resistance was analyzed using logistic regression analysis.RESULTS For the SCN1A rs121917953 T/A*(D188V)polymorphism,a significantly higher proportion of individuals with AT genotype were observed in the drug-resistant group as compared to the drug-responsive group.Additionally,a higher risk association was exhibited by AT genotype for drug resistance with an odds ratio of 3.51 and P value=0.017.For the SCN1A rs121918623 C/T*(T875M)polymorphism,no significant difference in genotype distribution was observed between the drug-resistant and drug-sensitive groups.CONCLUSION Our findings indicate that the SCN1A polymorphism D188V is associated with a higher risk of drug resistance for the AT variant as compared to the homozygous TT wild-type.Further research is needed at the functional level and in larger cohorts to determine the potential of these genes as a therapeutic target in epilepsy subjects.

基于Vague集和响应面模型的注塑工艺多目标优化

针对注塑工艺多目标优化问题,以塑件的翘曲变形量、顶出时体积收缩率和缩痕深度作为优化目标,选取熔体温度、模具温度、注射时间、保压压力、保压时间等工艺参数为试验因素,采用中心复合试验设计结合模流分析建立试验样本,利用Vague集方法计算各优化目标相似度,通过指标相关性的指标权重确定(CRITIC)法确定各优化目标影响权重,得到综合相似度;建立综合相似度与各工艺参数之间的响应面模型,运用灰狼算法进行工艺参数寻优,得到最优工艺参数组合。结果表明,将Vague集和响应面模型相结合的优化结果显著,为实际生产过程提供了有益参考。

基于Vague集犹豫量化的机舱团队协作式评估方法

针对现有机舱团队协作评估方法不统一且主观随意性太强的缺陷,提出一种基于Vague集犹豫量化的新型评估方法。从机舱团队协作的角度对影响评估的各因素进行提取,采用集合相似系数对重要协作指标量化,并采用C-OWA算子赋权法和变异系数法确定主客观权重,利用最小鉴别信息原理求得组合权重,结合Vague集的犹豫量化特点,通过机舱团队实际操作数据与Vague集评估标准得到各指标的定性评估Vague集,并利用集合相似度分析实现机舱团队协作的综合评估。实例计算结果表明:相对于传统的评估方法,在个体完成度的基础上加入具有犹豫团队协作因素的方法,能对评估结果的犹豫度进行较好地刻画,也能很好地实现定量与定性之间的转化,是一种有效且优越的机舱团队协作式评估方法。

Vagus effect on pylorus preserving gastrectomy

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Electrical stimulation of the vagus nerve protects against cerebral ischemic injury through an anti-inflammatory mechanism

Vagus nerve stimulation exerts protective effects against ischemic brain injury; however, the underlying mechanisms remain unclear. In this study, a rat model of focal cerebral ischemia was established using the occlusion method, and the right vagus nerve was given electrical stimula-tion （constant current of 0.5 mA; pulse width, 0.5 ms; frequency, 20 Hz; duration, 30 seconds; every 5 minutes for a total of 60 minutes） 30 minutes, 12 hours, and 1, 2, 3, 7 and 14 days after surgery. Electrical stimulation of the vagus nerve substantially reduced infarct volume, improved neurological function, and decreased the expression levels of tumor necrosis factor-α and in-terleukin-6 in rats with focal cerebral ischemia. The experimental findings indicate that the neuroprotective effect of vagus nerve stimulation following cerebral ischemia may be associated with the inhibition of tumor necrosis factor-α and interleukin-6 expression.

TRH microinjection into DVC enhances motility of rabbits gallbladder via vagus nerve

AIM To investigate the effects of TRH in DVC on motility of the gallbladder in rabbits. METHODS After fasted for 15h - 18h , rabbits were anesthetized with urethane (1 0g/kg) . Gallbladder pressure (GP) was measured by a frog bladder perfused with normal saline. RESULTS After microinjection of TRH (8 8nmol, 1μl ) into DVC, GP was raised and the frequency of phasic contraction of gallbladder (FPCGB) increased. All the doses of TRH (0 13, 0 25, 0 50, 0 80, 1 30nmol , 1μl ) injected into DVC could excite the motility of gallblader. As the dose of TRH was enlarged, the amplitude and duration of the reaction increased. Effects of TRH in DVC on motility of the gallbladder could be completely abolished by atropine ( 0 2mg/g , i.v.) or vagotomy, but could not be inhibited by phentolamine iv (1 5mg/g) or propranolol iv (1.5mg/g) or by transecting the spinal cord. CONCLUSION Thyrotropin releasing hormone in DVC can excite motility of gallbladder. This effect was mediated by vagus nerves and peripheral M receptor. Its physiological significance may be related to maintaining the phasic contraction of gallbladder in interdigestive period.

Electroacupuncture modulates the activity of the hippocampus-nucleus tractus solitarius-vagus nerve pathway to reduce myocardial ischemic injury

The hippocampus is involved in the regulation of the autonomic nervous system,together with the hypothalamus and brainstem nuclei,such as the paraventricular nucleus and nucleus tractus solitarius.The vagus nerve-nucleus tractus solitarius pathway has an important role in cardiovascular reflex regulation.Myocardial ischemia has been shown to cause changes in the autonomic nervous system,affecting the dynamic equilibrium of the sympathetic and vagal nerves.However,it remains poorly understood how the hippocampus communicates with brainstem nuclei to regulate the autonomic nervous system and alleviate myocardial ischemic tissue damage.A rat model of acute myocardial ischemia（AMI） was made by ligating the left anterior descending branch of the coronary artery.Three days before ischemia,the hippocampal CA1 region was damaged.Then,3 days after ischemia,electroacupuncture（EA） at Shenmen（HT7）-Tongli（HT5） was performed（continuous wave,1 m A,2 Hz,duration of 30 minutes）.Cluster analysis of firing patterns showed that one type of neuron was found in rats in the sham and AMI groups.Three types of neurons were observed in the AMI ＋ EA group.Six types of neurons were found in the AMI ＋ EA ＋ Lesion group.Correlation analysis showed that the frequency of vagus nerve discharge in each group was negatively correlated with heart rate（HR）（P 〈 0.05,r =-0.424）,and positively correlated with mean arterial pressure（MAP）（P 〈 0.05,r = 0.40987） and the rate-pressure product（RPP）（P 〈 0.05,r = 0.4252）.The total frequency of the nucleus tractus solitarius discharge in each group was positively correlated with vagus nerve discharge（P 〈 0.01,r = 0.7021）,but not with hemodynamic index（HR： P 〉 0.05,r =-0.03263; MAP： P 〉 0.05,r =-0.08993; RPP： P 〉 0.05,r =-0.03263）.Some neurons（Neuron C） were negatively correlated with vagus nerve discharge,HR,MAP and RPP in the AMI ＋ EA group（vagus nerve discharge： P 〈 0.05,r =-0.87749; HR： P 〈 0.01,r =-0.91902; MAP： P 〈 0.05,r =-0.85691; RPP： P 〈 0.01,r =-0.91902）.Some neurons（Neurons C,D and E） were positively correlated with vagus nerve discharge,HR,MAP and RPP in the AMI ＋ EA ＋ Lesion group（vagus nerve discharge： P 〈 0.01,r = 0.8905,P 〈 0.01,r = 0.9725,P 〈 0.01,r = 0.9054; HR： P 〈 0.01,r = 0.9347,P 〈 0.01,r = 0.9089,P 〈 0.05,r = 0.8247; MAP： P 〈 0.05,r = 0.8474,P 〈 0.01,r = 0.9691,P 〈 0.01,r = 0.9027; RPP： P 〈 0.05,r = 0.8637,P 〈 0.01,r = 0.9407,P 〈 0.01,r = 0.9027）.These findings show that the hippocampus-nucleus tractus solitarius-vagus nerve pathway is involved in the cardioprotective effect of EA at the heart meridian.Some interneurons in the nucleus tractus solitarius may play a particularly important role in the cardiomodulatory process.

Wake-promoting effects of vagus nerve stimulation after traumatic brain injury: upregulation of orexin-A and orexin receptor type 1 expression in the prefrontal cortex

Orexins, produced in the lateral hypothalamus, are important neuropeptides that participate in the sleep/wake cycle, and their expres- sion coincides with the projection area of the vagus nerve in the brain. Vagus nerve stimulation has been shown to decrease the amounts of daytime sleep and rapid eye movement in epilepsy patients with traumatic brain injury. In the present study, we investigated whether vagus nerve stimulation promotes wakefulness and affects orexin expression. A rat model of traumatic brain injury was established using the free fall drop method. In the stimulated group, rats with traumatic brain injury received vagus nerve stimulation （frequency, 30 Hz, current, 1.0 mA; pulse width, 0.5 ms; total stimulation time, 15 minutes）. In the antagonist group, rats with traumatic brain injury were intracerebroventricularly injected with the orexin receptor type 1 （OXIR） antagonist SB334867 and received vagus nerve stimulation. Changes in consciousness were observed after stimulation in each group. Enzyme-linked immunosorbent assay, western blot assay and immunohistochemistry were used to assess the levels of orexin-A and OX1R expression in the prefrontal cortex. In the stimulated group, consciousness was substantially improved, orexin-A protein expression gradually increased within 24 hours after injury and OX1R expres- sion reached a peak at 12 hours, compared with rats subjected to traumatic brain injury only. In the antagonist group, the wake-promoting effect of vagus nerve stimulation was diminished, and orexin-A and OX1R expression were decreased, compared with that of the stim- ulated group. Taken together, our findings suggest that vagus nerve stimulation promotes the recovery of consciousness in comatose rats after traumatic brain injury. The upregulation of orexin-A and OXIR expression in the prefrontal cortex might be involved in the wake-promoting effects of vagus nerve stimulation.

Gut-microbiome-brain axis:the crosstalk between the vagus nerve,alpha-synuclein and the brain in Parkinson's disease

This critical review of the literature shows that there is a close link between the microbiome,the gut,and the brain in Parkinson's disease.The vagus nerve,the main component of the parasympathetic nervous system,is involved in the regulation of immune response,digestion,heart rate,and control of mood.It can detect microbiota metabolites through its afferents,transferring this gut information to the central nervous system.Preclinical and clinical studies have shown the important role played by the gut microbiome and gut-related factors in disease development and progression,as well as treatment responses.These findings suggest that the gut microbiome may be a valuable target for new therapeutic strategies for Parkinson's disease.More studies are needed to better understand the underlying biology and how this axis can be modulated for the patient's benefit.

Efficacy of Vagus Nerve Stimulation (VNS) after Multiple Subpial Transections (MST) for Extra-Temporal Seizure Foci

Background: The effect of Vagus nerve stimulation (VNS) therapy following major resective surgeries has been reported. However, the effect of VNS therapy following multiple-subpial-transections (MST) has not been reported. The objective of this paper is to examine the beneficial effect of VNS therapy following MST. Methods: There are 22 patients aged 10 - 55 years. Male/female distribution is 11/11 and follow-up is 24 - 148 months (median of 120 months). Seizure foci were bilateral in 9 patients, multi-lobar (unilateral) in 12 patients and single-lobar in 1 patient. MST was performed over broad areas in and around the seizure foci. VNS implantation was done when the response to MST procedure was poor (1 patients), or there was recurrence of seizures (21 patients). Interval between MST and VNS implanttation varied from one month to three years (median of 2 years). Results: Thirteen patients (59%) are seizure free (Engel’ Class I), 8 (36.5%) have greater than 90% reduction in seizure frequency (Class II), and 1 (4.5%) has between 50% - 90% reduction in seizure frequency (Class III). Conclusion: The results show that VNS therapy produced meaningful improvement in seizure outcome in all patients with extra-temporal seizures that had inadequate response to MST.

Neuroprotective effects of vagus nerve stimulation on traumatic brain injury

Previous studies have shown that vagus nerve stimulation can improve the prognosis of trau- matic brain injury. The aim of this study was to elucidate the mechanism of the neuroprotective effects of vagus nerve stimulation in rabbits with brain explosive injury. Rabbits with brain ex- plosive injury received continuous stimulation （10 V, 5 Hz, 5 ms, 20 minutes） of the right cervical vagus nerve. Tumor necrosis factor-a, interleukin-l~ and interleukin-10 concentrations were detected in serum and brain tissues, and water content in brain tissues was measured. Results showed that vagus nerve stimulation could reduce the degree of brain edema, decrease tumor necrosis factor-a and interleukin-1β concentrations, and increase interleukin-10 concentration after brain explosive injury in rabbits. These data suggest that vagus nerve stimulation may exert neuroprotective effects against explosive injury via regulating the expression of tumor necrosis factor-a, interleukin-1 β and interleukin-10 in the serum and brain tissue.

Relationship between abnormal vagus nerve tension and basal ganglia cerebral infarction induced paroxysmal atrial fibrillation

Objective: To investigate the relationship between basal ganglia cerebral infarction and paroxysmal atrial fibrillation(PAF) caused by abnormal vagus nerve tension.Methods: A total of 1 483 cases of elder patients with cerebral infarction who received head CT or MRI examination during the period were enrolled, including 830 male and613 female, with the average age as 78 years. These cases were divided into basal infarction ganglia group(n = 1 045) and non-basal ganglia infarction group(n = 438)according to the anatomic site of cerebral infarction. The differences of the incidence of PAF, left atrial diameter and heart rate variability were compared between the two groups.Results: In basal ganglia infarction group, the incidence rate of PAF was significantly higher than that of non-basal ganglia infarction group(P < 0.05). The incidence trend of cerebral infarction in basal ganglia was age-related, in the >79 years basal ganglia cerebral infarction group, the incidence of PAF was significantly higher than that of nonbasal ganglia infarction group(P < 0.05). There was no significant difference in the left atrial diameter between the basal ganglia infarction group and non-basal ganglia infarction group. Basal ganglia cerebral infarction patients with high PAF had higher heart rate variability than non-basal ganglia infarction group.Conclusion: Elderly patients with basal ganglia infarction have high incidence of PAF.Sympathetic nerve damage in cerebral basal ganglia, increased vagal tension and cardiac vagal tension are the direct causes of PAF. The results indicates that the increased central vagal nerve tension mediated PAF probably is an indication of supplying sympathetic neurotransmitter or cardiac vagal denervation treatment.