男性攻击性精神分裂症患者杏仁核功能连接的磁共振研究

目的:探讨男性攻击性精神分裂症患者是否存在杏仁核与其他脑区功能连接的异常.方法:对有攻击行为和没有攻击行为的男性精神分裂症患者各13例进行静息状态下功能磁共振成像.结果:与非攻击组相比,攻击组双侧额中回、右侧额上回、右侧脑岛、右侧顶上小叶、右侧扣带回等脑区与左侧杏仁核功能连接增强;双侧额上回、额中回、双侧颞上回、右侧颢中回等脑区与右侧杏仁核功能增强.结论:杏仁核与多个脑区之间特别是与额上回、额中回的功能连接增强可能与男性精神分裂症患者的攻击行为有关.     

杏仁核与创伤后应激障碍发病机制的相关性

创伤后应激障碍(PTSD)是指由于异常威胁性或灾难性心理创伤导致延迟出现和长期持续的精神障碍。杏仁核是大脑中的"恐惧中枢",与创伤性记忆和应激时HPA轴的激活联系密切。PTSD患者有强烈的恐惧和惊吓反应,血中糖皮质激素浓度反常低下,下丘脑-垂体-肾上腺轴(HPA)轴调节紊乱。杏仁核可通过糖皮质激素受体(GR)和盐皮质激素受体(MR)调节激活HPA轴,增加糖皮质激素的释放。PTSD导致杏仁核神经元细胞凋亡,凋亡相关基因Bax和Bcl-2比值增大时,神经细胞出现凋亡。PTSD引发杏仁核神经元长时程增强(LTP),杏仁核是恐惧形成和表达的关键中枢。在恐惧条件反射的形成过程中,杏仁核发生LTP,表明LTP是反应PTSD发生机制的重要指标。PTSD引致乙酰胆碱酯酶(AChE)活性降低,乙酰胆碱增多,恐惧增强;PTSD导致杏仁核神经元MR、GR及MR/GR发生改变,激活HPA轴,导致HPA轴调节紊乱。     

Expression pattern of neural synaptic plasticity marker-Arc in different brain regions induced by conditioned drug withdrawal from acute morphine-dependent rats

Aim： The immediate early gene Arc （activity-regulated cytoskeletal-associated protein） mRNA and protein are induced by strong synaptic activation and rapidly transported into dendrites, where they localize at active synaptic sites. Thus, the Arc mRNA and protein are proposed as a marker of neuronal reactivity to map the neural substrates that are recruited by various stimuli. In the present study, we examined the expression of Arc protein induced by conditioned naloxone-precipitated drug withdrawal in different brain regions of acute morphine-dependent rats. The objective of the present study was to address the specific neural circuits involved in conditioned place aversion （CPA） that has not yet been well characterized. Methods： Place aversion was elicited by conditioned naloxone-precipitated drug withdrawal following exposure to a single dose of morphine. An immunohistochemical method was employed to detect the expression of Arc, which was used as a plasticity marker to trace the brain areas that contribute to the formation of the place aversion. Results： Marked increases in Arc protein levels were found in the medial and lateral prefrontal cortex, the sensory cortex, the lateral striatum and the amygdala. This effect was more pronounced in the basolateral amygdala （BLA）, the central nucleus of the amygdala （CeA）, and the bed nucleus of the striatal terminals （BNST） when compared with the control group. Conclusion： Our results suggest that these brain regions may play key roles in mediating the negative motivational component of opiate withdrawal.     

抑郁症患者情绪图片反应特征及杏仁核反应模式的研究

Objective To explore the behavioral and related amygdaiar temporal response to emotional pictures in individuals with major depressive disorder(MDD).Methods Functional magnetic resonance imaging(fMRI)was adopted to examine the neural substrates of emotional pictures processing in 12 first-episode unmedicated MDD subjects(MDD)and 13 healthy controls(HC).Analyses were focused on the temporal dynamics of the blood-oxygen level dependant(BOLD)signal change in the amygdala across blocks of positive,neutral and negative emotional pictures.The crude score to emotional pictures was also recorded.Results(1)The crude score wag(6.6 ±0.2)to positive pictures and(4.7 ±0.1)to neutral pictures in depressed subjects,lower than that in HC(P＜0.01),and(3.4 ±0.3)to negativc pictures in depressed subjects,which was higher than that in HC(2.2±0.2,P＜0.01).(2)The bilateral amygdala showed attenuated and delayed response to the positive pictures.in which the right amygdala showed"group×time"interaction effect to positive pictures(P=0.002).For the negative pictures,there was"group×time"interaction effect in the left amygdala(P=0.008)and group main effect in the right amygdaia(P=0.007),with the attenuated BOLD signal change in MDD group.Conclusions It suggests that amygdala is one of the key neural substrates to the character of the depressed mood or loss of interest in individuals with MDD.Depressed subiects show the attenuated and blunted behavioral and amygdala response to emotional stimuli,which support the hypothesis of the unspecially blunted emotional response in major depressive disorder.     

White matter connectivity damage secondary to hippocampal and amygdala target injuries in acute limbic encephalitis Diffusion tensor image and voxel-based morphometry paired study

BACKGROUND： Limbic encephalitis is a rare syndrome that specifically affects the limbic system. Magnetic resonance imaging （MRI） has been typically used to detect brain changes in this disease. However, the mechanisms of limbic encephalitis-related white matter damage remain poorly understood. OBJECTIVE： To characterize white matter connectivity changes secondary to injuries of the limbic system in limbic encephalitis through combined application of diffusion tensor imaging （DTI） and voxel-based morphometry. DESIGN, TIME AND SETTING： A non-randomized, controlled, clinical, neuroimaging, DTI study was performed at the Department of Radiology, West China Hospital in December 2008. PARTICIPANTS： A male, 46-year-old, limbic encephalitis patient, as well as 11 age- and gender-matched healthy volunteers, were enrolled in the present study. METHODS： MRI was performed on the limbic encephalitis patient using a 3.0T MR scanner. Three-dimensional SPGR Tl-weighted images and DTI were acquired in the patient and controls. Data were analyzed using Matlab 7.0 and SPM2 software. MAIN OUTCOME MEASURES： Results from routine MRI scan with contrast enhancement of patient, as well as fractional anisotropy and mean diffusivity value map differences between patient and controls. RESULTS： Significant symmetric MRI signal intensity abnormalities were observed with routine MRI Affected bilateral hippocampi and amygdala exhibited hypointense signals in TIWI and hyperintense signals in T2 images. The DTI study revealed decreased fractional anisotropy values in the bilateral alveus and fimbria of the hippocampus, bilateral internal and external capsules, white matter of the right prefrontal area, and left corona radiate in the patient compared with normal controls （P 〈 0.001） Significantly increased fractional anisotropy, mean diffusivity, or decreased mean diffusivity were not observed in the patient, compared with controls. CONCLUSION： Secondary white matter damage to the hippocampal afveus and fimbria was apparent in the limbic encephalitis patient. In addition, other white matter fiber injuries surrounded the limbic structures, which were not attributed to secondary limbic system injuries.     

大鼠岛叶电刺激点燃癫痫模型超微结构观察

目的:通过对电刺激岛叶点燃癫痫模型岛叶及同侧杏仁核神经元超微结构的观察,探讨在癫痫发作中发作起源的神经元变化特征及其与邻近结构的相互关系.方法:建立岛叶电刺激点燃癫痫发作模型,点燃成功后大鼠断头取脑,观察超微结构变化.结果:岛叶及同侧杏仁核神经元超微结构表现出凋亡特征,但杏仁核病理改变程度较轻.结论:癫痫的超微结构变化...     

心理应激与夜磨牙关系的研究进展

夜磨牙因其发病率较高、严重影响口腔健康,尚缺乏行之有效的治疗措施,日益成为口腔修复学临床与研究工作的重点问题.近年来,国内外有关夜磨牙发病机理的深入研究发现,心理应激已成为夜磨牙的最重要诱/病因之一.在心理应激诱发/导致夜磨牙的过程中,中枢与外周神经系统均参与其中,其机制较为复杂.本史将就心理应激与夜磨牙关系的研究进展作一综述,旨在探讨心理应激引发夜磨牙的可能机制,完善夜磨牙的发病机理,进而能够提出切实可行的临床应对措施.     

基于高分辨率MRI的正常中国成人杏仁核体积测量

目的应用高分辨率磁共振和三维体积分析软件（Aquariusws）测量中国正常成人杏仁核的体积。方法对43例健康成年中国人行大脑T1加权三维磁化强度预备梯度回波序列扫描,应用Aquariusws软件确定和测量杏仁核边界和体积。结果经Aquariusws软件对高分辨率MRI图像进行三维重建后,能清楚显示杏仁核的边界。杏仁核平均体积：右侧1596.525mm3（男1566.773mm3,女1604.877mm3）,左侧1564.318mm3（男1623.987mm3,女1545.244mm3）。双侧、男女杏仁核体积无统计学差异（P〉0.05）。结论基于高分辨率磁共振图像和三维体积分析软件（Aquariusws）可以动态三维确认杏仁核轮廓,进而准确测定其体积。     

大鼠岛叶与杏仁核电点燃癫痫模型的相关性研究

目的 电刺激Sprague-Dawley大鼠岛叶、杏仁核及同时刺激岛叶、杏仁核建立复杂部分性癫痫模型,探讨岛叶癫痫的可能发病机制.方法 健康雄性SD大鼠60只,随机分成三组:岛叶点燃组(IK)、杏仁核点燃组(AK)、岛叶杏仁核同时点燃组(BK).分别将双极电极植入左侧岛叶、左侧杏仁核和同时植入岛叶杏仁核;测定后放阈后每日给予两次电刺激,刺激参数:强度为后放阈1.5倍,频率60 Hz,波宽1 ms,持续时间1 s.结果 岛叶组和杏仁核组后放阈值差异有统计学意义(P<0.05);三组点燃时间差异有统计学意义,岛叶组点燃最快,岛叶杏仁核同时点燃组点燃最慢(P<0.05);三组点燃率无明显差异.结论 岛叶是一个癫痫症状发作区;岛叶癫痫的发生、发展与杏仁核点燃存在差异;同时点燃表现为点燃的拮抗作用.     

经颞下回-侧脑室入路选择性海马杏仁核切除术治疗内侧颞叶癫痫

目的：探讨经颞下回-侧脑室入路选择性杏仁核海马切除术治疗内侧颞叶癫痫的手术方法、疗效及并发症。方法：确诊为药物难治性内侧颞叶癫痫的62例患者,经颞部锁孔开颅,切除中前段颞下回,进入颞角前外侧区,选择性切除杏仁核海马及海马旁回等内侧颞叶结构。结果：62例患者术后随访至少2年时间（24—80个月）。无严重手术并发症,45例（72．6％）发作完全消失（EngelⅠ级）。结论：经颞下回侧脑室入路选择性杏仁核海马切除术是治疗内侧颞叶癫痫的有效方法,手术创伤小,可妥善保护语言区和视放射。安全性高。