Effect of nitric oxide on the expression of apelin receptor mRNA in rat caudate nucleus

Objective To investigate the effect of nitric oxide （NO） on the expression of apelin receptor mRNA, as well as their correlation, in the caudate nucleus of rat. Methods L-Arginine （L-Arg）, N^G-nitro-L-arginine methyl ester （L-NAME） and normal saline （NS） was separately microinjected into rat caudate nucleus. Expressions of neuronal NO synthase （nNOS） mRNA and apelin receptor mRNA were detected by RT-PCR at 4, 8, 12, 24 and 48 h after microinjection, and their correlation was determined. Results The expressions of nNOS mRNA and apelin receptor mRNA were both significantly increased after microinjection of L-Arg, but significantly decreased after microinjection of L-NAME compared with the NS control group. The nNOS mRNA had a positive correlation with the expression of apelin receptor mRNA after microinjection of L-Arg and L-NAME. Conclusion The activity of NOS in the central nervous system, especially in the caudate nucleus, is one of the key factors for NO to exert many kinds of biological actions, such as modulation of central pain, as a neurotransmitter. The neurobiological action of NO in rat caudate nucleus may be associated with apelin receptors.

M-CHOLINOCEPTORS IN CAUDATE NUCLEUS PARTICIPATE IN SmI ORIGINATING DESCENDING MODULATION OF PARAFASCICULARNEURONS IN ACUPUNCTURE ANALGESIA

The present study was undertaken to investigate whether M-cholinoceptors in caudate nucleus (Cd) were implicated in cortical sensorimotor area I (SmI) originating descending modulation of activities in thalamic parafascicular nuclei (Pf) in acupuncture analgesia (AA). It was found that following bilateral microinjection of atropine into Cd head electroacupuncture (EA) (n=12) or glutamate (Glu) applied at SmI (n=12) did not affect the nociceptive responses of Pf neurons (P>0. 05),while in the saline control groups EA (n=11) or Glu at SmI (n=12) obviously inhibited nociceptive responses of Pf neurons (P<0. 05). There were significant differences in the effect of EA or Glu at SmI between atropine and saline groups (ANOVA, P<0. 05). Together with our previous findings demonstrating the participation of SmI originating descending modulation of Pf neurons in AA, the present investigation indicates that M-cholinoceptors are involved in mediating SmI originating descending modulation of Pf neurons in AA.

Proton magnetic resonance spectroscopy of the anterior cingulate gyrus and caudate nucleus in schizophrenia patients versus healthy controls

Proton magnetic resonance spectroscopy （^1 H-MRS） permits the assessment of cerebral neurometabolites, such as N-acetylaspartate, choline, and creatine, in vivo and has been used to study schizophrenia. The present study used ^1H-MRS to compare the spectroscopy change of N-acetylaspartate, creatine, and choline metabolite levels in the anterior cingulate and caudate nucleus of both schizophrenia patients and healthy controls, as well as between the left and right cerebral hemispheres in the schizophrenia patients. Results showed that N-acetylaspartate and creatine metabolite levels in the left anterior cingulate gyrus were significantly lower in the schizophrenia patients than in the healthy controls, indicating hypometabolism. In addition, choline concentration in the left caudate nucleus of schizophrenia patients was significantly lower than in the right caudate nucleus, indicating that it is necessary to study the cerebral lateralization of ^1H-MRS in schizophrenia patients.

EFFECT OF ELECTROACUPUNCTURE ON DISCHARGES OF PAIN-REACTION NEURONS IN CAUDATE NUCLEUS AND PARAFACICULAR NUCLEUS IN RATS WITH CEREBRAL HEMORRHAGE

Objective: To study the bidirectional adjustment effe ct of ele ctroacupuncture (E A) on the electrical activities of neurons in caudate nucleus (CN) and parafasci cular nucleus (PFN) in rats with acute cerebral hemorrhage (ACH). Methods: ① 32 male Wistar rats were evenly randomize d into normal, EA+normal, model and model +EA groups for observing the effect of EA on pain reaction; ② another 40 male Wi star rats were equally randomized into control, saline, model and EA groups for comparing the effects of EA on discharges of pain-reaction neurons in CN and P FN . ACH model was established by intracerebral injection of the rat’s own arteria l blood sample (30μL) into CN and PFN. Pain reaction was tested by using tail -flicking (TF) reflex induced by radiation-heat irradiation. Extra-cellular d ischarges of neurons of CN and PFN were recorded by using glass micropipettes. E A (1 V, 15 Hz and duration of 10 min) was applied to "Baihui"(百会 GV 20) and "Taiyang" (太阳 EX-HN 5). Frequency of discharges of CN and PFN neurons was calculated be fore and after intracerebral injection of blood sample, heat nociceptive stimula tion and EA respectively. Results: Compared with con trol group and pre-EA in the same group, TF latency (TFL) values of normal rats increased significantly; compared w ith pre-injection of blood, TFL of model group also increased pronouncedly ( P<0.0 1). In comparison with model group, TFL values of EA group decreased significant ly (P<0.01), indicating that EA of GV 20 and EX-HN 5 could suppress ACH induced increase of TFL. In ACH rats, the latency of pain-excitement response of disch ar ges of CN and PFN neurons increased significantly, while the net increase values of pain-excitement response decreased significantly in model group (P< 0.05～0.01 ), the duration of pain-inhibitory response and the net decrease values of dis ch arges of CN and PFN neurons increased clearly. Comparison between model and EA groups showed that the latency values of the pain-excitement reaction of disch ar ges of CN and PFN neurons in EA group were significantly lower than those in mod el group (P<0.01), while the net increase values of discharges of CN and PFN neu rons in EA group were considerable higher than those in model group (P< 0.01); th e latency and net decrease values of pain-inhibitory CN and PFN neurons in EA gr oup were clearly lower than those in model group. It indicated that EA could pro l ong the latency of pain-excitatory reaction and shorten the duration of pain-i nhi bitory reactions of the neurons induced by cerebral hemorrhage and raise the exc itement degree of CN and PFN neurons. Conclusion: EA can reduce the excitability of pain-excitement neurons (PEN) and lower the inhibitory degree of pain -inhibitory neurons (PIN) in both CN and PFN, an d thus possesses a bidirectional regulation effect on cerebral hemorrhage-induced c hanges of the electrical activities of neurons in both CN and PFN.

EFFECT OF INTRAVENTRICULAR INJECTION OF DOPAMINE ON PAIN-EXCITATION AND PAIN-IN HIBITION NEURONS IN CAUDATE NUCLEUS OF RAT

Many experiments have shown that the central dopaminergic system is closely related with acupuncture and morphine analgesia. However, there are certain divergences among different authors. Some reported that the central dopaminergic system abates acupuncture and morphine analgesia while others reported that the dopaminergic system coorperates with acupuncture analgesia. The aim of this work is to go further into the relationships of the dopaminergic system in the caudate nucleus (N. Cd.) with pain sensation.

早期帕金森病触觉刺激异常激活脑区意义初探

目的:探求原发性帕金森病(PD)触觉功能脑区异常激活程度是否与病情严重度直接相关;对PD触觉脑功能改变与尾状核功能缺陷间的联系提供可能的影像学依据;对前额叶的激活在PD脑功能机制中所起的作用做出可能的解释。方法:21名早期PD患者,平均年龄(60.43±9.65)岁;22名年龄相匹配的正常志愿者,平均年龄(59.23±11.12)岁。所有患者进行统一PD量表(UPDRS)评分,以评价病情严重程度。首先通过触觉任务的fMR I研究,确定PD患者相较于正常人激活增强和减弱的脑区。接着将上述脑区作为感兴趣区(ROI),提取出每个PD患者执行触觉任务时各ROI平均BOLD信号强度,并计算信号变化百分比。将各ROI的信号变化与患者病情严重程度作相关分析,同时作ROI之间相关分析。结果:PD患者右侧初级感觉及运动区,右侧辅助运动区,双侧楔前叶,双侧枕叶视觉皮层,左侧颞中回及双侧尾状核的激活较对照组降低;右侧前额叶及右侧尾状核激活较对照组增高。右侧辅助运动区的信号变化与UPDRS评分呈负相关。双侧尾状核与异常激活脑区的信号变化呈现正相关。右侧前额叶与激活降低脑区的信号变化呈现正相关。结论:早期帕金森患者接受触觉刺激时,辅助运动区的信号改变可以提示病情严重程度。尾状核在PD触觉神经功能改变中应该起着重要作用。前额叶激活增加的原因可能并不是代偿作用,而更可能是PD患者神经功能损害的一种体现。

Differential effects of dopamine on pain-related electric activities in normal rats and morphinistic rats

Objective To investigate the influence of dopamine （DA） and DA receptor＇s antagonist on the transmission of noxious information in the central nervous system of normal rats or morphinistic rats. Methods The influence of DA on the electric activity of the pain-excited neuron （PEN） in the caudate nucleus （Cd） of normal rats or morphinistic rats was recorded after the sciatic nerve was noxiously stimulated. Results DA shortened the average latency of the evoked discharge of PEN in the Cd of normal rats, indicating that DA could increase the activity of PEN and pain sensitivity in normal rats. This effect could be inhibited by Droperidol. DA increased the average latency of the evoked discharge of PEN in the Cd of morphinistic rats, indicating that DA could inhibit the activity of PEN and pain sensitivity in morphinistic rats. Conclusion The responses to painful stimulation were completely opposite between normal rats and morphinistic rats after the intracerebroventricular injection of DA.

脑立体定向建立C_6大鼠脑胶质瘤模型

目的为脑胶质瘤的治疗研究提供实验基础 ,建立可靠的动物模型。方法采用脑立体定向术 ,在SD大鼠脑尾状核接种C6细胞。术后观察大鼠的生存期 ,并采用MRI及病理学检查方法 ,动态观察肿瘤生长情况。结果接种 1周后 ,按不同时间行MRI、病理解剖学及GFAP、S - 10 0免疫组织化学检查 ,均显示颅内肿瘤形成。结论该方法建立的脑胶质瘤具有与人脑胶质瘤生长相似的特性 ,肿瘤形成时间短 ,生存期稳定 ,适合于脑胶质瘤实验治疗研究的需要。

计算机对猫脑结构重建的研究 Ⅲ.脑外形、尾核和海马三维结构的重建

实验用体重2.0kg～3.5kg猫12只,切1.0mm脑厚片,用MULLGAN法染色,拍照。读取各片外脑、尾核及海马外形数据,输入Micro VAXⅡ计算机,在其联机AR_(002)AA黑白终端上显示图形,通过X、Y、Z轴分别旋转不同角度显示其立体结构。本工作成功地重建了脑外形、尾核及海马的三维结构,为神经解剖、神经生理及神经药理等学科的研究提供了资料。

Regional gray matter abnormality in hepatic myelopathy patients after transjugular intrahepatic portosystemic shunt: a voxel-based morphometry study

Hepatic myelopathy is a complication seen in patients with chronic liver failure with physiologic or iatrogenic portosystemic shunting. The main symptom is progressive lower limb dyskinesia. The role of the brain motor control center in hepatic myelopathy is unknown. This study aimed to investigate the gray matter changes in patients with hepatic myelopathy secondary to transjugular intrahepatic portosystemic shunt and to examine their clinical relevance. This was a cross-sectional study. Twenty-three liver failure patients with hepatic myelopathy(hepatic myelopathy group), 23 liver failure patients without hepatic myelopathy(non-hepatic myelopathy group) after transjugular intrahepatic portosystemic shunt, and 23 demographically matched healthy volunteers were enrolled from March 2014 to November 2016 at Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China. High-resolution magnetization-prepared rapid gradient-echo brain imaging was acquired. Group differences in regional gray matter were assessed using voxel-based morphometry analysis. The relationship between aberrant gray matter and motor characteristics was investigated. Results demonstrated that compared with the non-hepatic myelopathy group, gray matter volume abnormalities were asymmetric, with decreased volume in the left insula(P = 0.003), left thalamus(P = 0.029), left superior frontal gyrus(P = 0.006), and right middle cingulate cortex(P = 0.021), and increased volume in the right caudate nucleus(P = 0.017), corrected with open-source software. The volume of the right caudate nucleus in the hepatic myelopathy group negatively correlated with the lower limb clinical rating of the Fugl-Meyer Assessment(r = –0.53, P = 0.01). Compared with healthy controls, patients with and without hepatic myelopathy exhibited overall increased gray matter volume in both thalami, and decreased gray matter volume in both putamen, as well as in the globus pallidus, cerebellum, and vermis. The gray matter abnormalities we found predominantly involved motor-related regions, and may be associated with motor dysfunction. An enlarged right caudate nucleus might help to predict weak lower limb motor performance in patients with preclinical hepatic myelopathy after transjugular intrahepatic portosystemic shunt. This study was approved by the Ethics Committee of Xijing Hospital, Air Force Military Medical University(Fourth Military Medical University), China(approval No. 20140227-6) on February 27, 2014.

EFFECT OF ELECTROACUPUNCTURE OF SCALP-POINTS ON ABNORMAL DISCHARGES OF NEURONS AROUND THE CEREBRAL HEMORRHAGE FOCUS IN THE RAT

Objective: To study the mechanism of electroacupuncture (EA) of scalp-points for regulating abnormal discharges of neurons in different regions around the cerebral hemorrhage focus by using neuro-electrophysiological methods. Methods: 80 Wistar rats (anesthetized with 20% urethane 1 g/kg, i.p.) were randomly divided into normal, saline, model and EA groups, with 20 cases in each group. Cerebral hemorrhage model was established by intracerebral injection of the rat’s own arterial blood sample (40 uL). In rats of saline group, the same volume of saline was given for intracerebral injection. Extracellular electrical activity of neurons of the caudate nucleus and parafascicular nucleus and Tail flicking latency (TFL) were used as the indexes. “Baihui”(百会 GV 20) and “Taiyang”(太阳 EX-HN 5) were punctured from GV 20 towards EX-HN 5 with filiform needles and stimulated electrically with stimulating parameters of strength of 1 V, frequency of 15 Hz and duration of 15 min. Results: Compared with normal group, TFL values of model group and EA group increased significantly (P<0.01); and compared with model group, those of EA group decreased significantly (P<0.01), suggesting that the pain threshold increased significantly in cerebral hemorrhage rats while after acupuncture stimulation, it lowered strikingly. Compared with normal and saline groups, the latency values of the pain excitement and inhibitory responses of the cellular discharges of the caudate and parafascicular nuclei in model and EA groups increased significantly (P<0.05～0.01), while after EA, it recovered apparently (P<0.01), showing an apparent regulative effect of EA on the abnormal changes of discharges of neurons around the cerebral hemorrhage focus. Conclusion: Scalp-acupuncture possesses an apparent regulatory effect on the abnormal electrical activity of neurons around the cerebral hemorrhage focus which may favor the early recovery of functional activity of neurons near the focus tissues.