替来他明诱导大鼠中枢神经系统c-fos基因的表达

本研究旨在观察替来他明麻醉后大鼠中枢神经系统c-fos基因的表达,了解替来他明在中枢神经系统的作用部位,探讨替来他明对中枢神经系统的作用机制。72只SD大鼠,随机分为生理盐水组、给药后10、30、60、90、100、120和180 min组,每组9只。腹腔注射替来他明50 mg.kg-1后,分别于给药前(生理盐水组)和给药后10、30、60、90、100、120和180 min经4%多聚甲醛(0.1 mol.L-1,PB,pH7.4)灌注后,取脑,将脑分为大脑皮层、海马、丘脑、小脑、脑干5个脑区,置于20%蔗糖溶液中24 h(4℃)脱水。冰冻切片,片厚10μm,按照Elivision法进行免疫组化染色,观察鉴别Fos阳性神经元并做阳性神经元计数。结查显示,对照组中仅发现少量Fos阳性神经元,试验组中Fos阳性神经元在大脑皮层、海马、丘脑、小脑、脑干内都有表达。替来他明腹腔注射10 min后Fos阳性神经元表达开始增加,60 min表达至高峰,90 min表达下降,180 min下降至基线水平,与给药前相比无显著性差异(P0.05)。结果提示,替来他明能诱导大鼠大脑皮层、海马、丘脑、小脑、脑干c-fos基因的表达,大脑皮层、海马、丘脑、小脑和脑干是替来他明的作用位点。     

替来他明及小型猪复方麻醉剂对大鼠不瓦脑区一氧化氮及一氧化氮合酶的影响

目的-研究一氧化氮（N0）、一氧化氮合酶（NOs）在替来他明及小型猪复方麻醉剂（XFM）全麻分子机理中可能的作用。方法-SD大鼠96只，先随机均分替来他明组和XFM组，每组又随机均分为对照组、麻醉组、恢复Ⅰ组和恢复Ⅱ组。用比色法分别测定各脑区的NO产量和NOS活性。结果-ip替来他明30mg／kg后，在麻醉组大脑皮层、海马及丘脑的NOS活性受到明显抑制，且使NO产量显著减少（与对照组相比，P〈0．05）。在恢复Ⅰ组上述脑区NO产量、NOS活性呈现不同程度恢复，到恢复Ⅱ组时明显恢复（与对照组相比，P〉0．05）。在替来他明麻醉全过程中小脑和脑于NOS活性无明显变化。大鼠ipXFM0．5mL／100g后，在麻醉组大脑皮层、小脑和丘脑的NOS活性明显受到抑制，且使NO产量显著减少（与对照组相比，P〈0．01）。而在恢复Ⅰ组、Ⅱ组上述3个脑区的NO产量、NOS活性明显恢复（与对照组相比，P〉0．05）。在XFM麻醉全过程中海马和脑干NOS活性无明显变化。结论-NO、NOS参与了替来他明及XFM全麻作用产生的分子学机理的调控。替来他明全麻作用可能与抑制大脑皮层、海马和丘脑等脑区的NO产量、NOS活性相关。而XFM全麻作用可能与抑制大脑皮层、小脑和丘脑等脑区的N0产量、NOS活性相关。     

替来他明及小型猪复方麻醉剂对大鼠不同脑区一氧化氮及一氧化氮合酶的影响

目的-研究一氧化氮(NO)、一氧化氮合酶(NOS)在替来他明及小型猪复方麻醉剂(XFM)全麻分子机理中可能的作用.方法-SD大鼠96只,先随机均分替来他明组和XFM组,每组又随机均分为对照组、麻醉组、恢复Ⅰ组和恢复Ⅱ组.用比色法分别测定各脑区的NO产量和NOS活性.结果-ip替来他明30 mg/kg后,在麻醉组大脑皮层、海马及丘脑的NOS活性受到明显抑制,且使NO产量显著减少(与对照组相比,P<0.05).在恢复Ⅰ组上述脑区NO产量、NOS活性呈现不同程度恢复,到恢复Ⅱ组时明显恢复(与对照组相比,P＞0.05).在替来他明麻醉全过程中小脑和脑干NOS活性无明显变化.大鼠ip XFM 0.5 mL/100g后,在麻醉组大脑皮层、小脑和丘脑的NOS活性明显受到抑制,且使NO产量显著减少(与对照组相比,P<0.01).而在恢复Ⅰ组、Ⅱ组上述3个脑区的NO产量、NOS活性明显恢复(与对照组相比,P＞0.05).在XFM麻醉全过程中海马和脑干NOS活性无明显变化.结论-NO、NOS参与了替来他明及XFM全麻作用产生的分子学机理的调控.替来他明全麻作用可能与抑制大脑皮层、海马和丘脑等脑区的NO产量、NOS活性相关.而XFM全麻作用可能与抑制大脑皮层、小脑和丘脑等脑区的NO产量、NOS活性相关.     

乳化异氟醚对大鼠不同脑区nAChRs表达的影响

为探讨乳化异氟醚对大鼠不同脑区nAChRs表达的影响,采用18只Wistar大鼠随机分为对照组、麻醉组和恢复组,应用乳化异氟醚通过尾静脉途径给药,对大鼠进行麻醉,采用免疫组织化学的方法,观察鉴别不同脑区中nAChRs表达的阳性细胞,并作阳性细胞计数。结果显示,大鼠注射乳化异氟醚后大脑皮层和海马的nAChRs的阳性细胞数显著下降,而小脑和脑干的nAChRs阳性细胞数显著增加,提示乳化异氟醚能够抑制大脑皮层和海马nAChRs的表达,诱导小脑和脑干nAChRs的表达,nAChRs可能是乳化异氟醚产生全麻作用的靶位之一。     

小型猪复合麻醉颉颃剂对大鼠各脑区p-p38蛋白及c-myc mRNA表达的影响

旨在研究小型猪复合麻醉颉颃剂对大鼠不同脑区p-p38蛋白及c-myc mRNA表达的影响,探讨小型猪复合麻醉颉颃剂的催醒机制。将18只大鼠随机分为C组(对照组)、J组(麻醉颉颃剂组)。J组又分为2个亚组,即J1组(注射小型猪专用复合麻醉颉颃剂5min)、J2组(注射小型猪专用复合麻醉颉颃剂1h)。各组大鼠到达相应的时间点后断头处死,分离大脑皮层、小脑、海马、脑干和丘脑,用Western blot的方法检测p-p38蛋白的表达量,实时荧光定量PCR方法检测c-myc基因mRNA的转录量。试验结果显示大鼠大脑皮层、丘脑和脑干的p-p38蛋白和c-myc mRNA的相对表达量显著升高,而小脑和海马的p-p38蛋白和c-myc mRNA的相对表达量显著降低。综合试验结果,小型猪复合麻醉颉颃剂能够影响p-p38蛋白和c-myc mRNA的表达,这可能是其产生催醒作用的机制之一。     

小型猪复合麻醉剂对大鼠中枢神经系统p-p38MAPK蛋白表达的影响

为研究小型猪复合麻醉剂(XFM)对大鼠中枢神经系统p-p38蛋白表达的影响,将30只大鼠分为对照组(C组)和麻醉剂组(M组),M组又分为4个亚组:M1组(注射XFM后大鼠翻正反射消失即刻)、M2组(注射XFM后大鼠翻正反射消失后1h)、M3组(注射XFM后大鼠翻正反射恢复即刻)和M4组(注射XFM后大鼠翻正反射恢复后1h),各组大鼠到达预定的时间点后分别采取脑组织,应用RT-PCR法检测脑内p38 mRNA转录量,应用Western blot方法检测中枢神经系统中p-p38蛋白的表达量。大鼠注射XFM后,与对照组比较,试验组大鼠大脑皮层和丘脑p38mRNA转录量显著降低(P0.05),在苏醒过程中有所恢复,但仍显著低于对照组(P0.05);大脑皮层和丘脑内p-p38蛋白的相对表达量,在M1、M2组的时间点显著低于对照组(P0.05或P0.01);大鼠注射XFM后,与对照组比较,试验组大鼠小脑、海马、脑干内p38mRNA转录量显著升高(P0.05),在苏醒过程中仍显著高于对照组(P0.05);小脑、海马、脑干内p-p38蛋白的表达量,在M1组、M2组、M3组显著升高,与对照组相比差异显著(P0.05或P0.01),在M4组表达量下降,与对照组相比差异不显著(P0.05)。结果表明,XFM诱导大鼠大脑皮层、丘脑内p38 mRNA及p-p38蛋白表达下调,p38 mRNA及磷酸化蛋白的改变可能是XFM作用的机制之一。     

鹿特异性复合麻醉剂对大鼠不同脑区ATP酶活性的影响

为研究鹿特异性复合麻醉剂麻醉与大鼠各脑区突触体ATP酶活性的关系,探讨其麻醉机理。将20只SD大鼠分为对照组和麻醉组,对照组大鼠腹腔注射30mL/kg生理盐水,试验组腹腔注射30mg/kg鹿特异性复合麻醉剂,采集大鼠各脑区,利用比色法测定脑区内Na＋-K＋-ATP、Ca2＋-AT P和Mg2＋-ATP酶活性。结果显示,药物作用后大鼠大脑皮层和脑干Na＋、K＋-ATP酶活性与对照组比较降低显著（P〈0.05或P〈0.01）,小脑、脑干和海马Ca2＋-ATP酶活性与对照组比较显著降低（P〈0.05或P〈0.01）,大脑Mg2＋-AT P酶活性低于对照组（P〈0.05或P〈0.01）。结果表明,麻醉引起大鼠大脑皮层、脑干中Na＋-K＋-ATP酶活性降低,大脑皮层中Mg2＋-ATP酶活性低,小脑、脑干和海马脑区中Ca2＋-ATP酶活性降低可能是鹿特异性复合麻醉剂麻醉作用的机理之一。     

小型猪复合麻醉剂对大鼠不同脑区LKB1基因mRNA转录和p-LKB1蛋白表达的影响

旨在研究小型猪复合麻醉剂(XFM)对大鼠不同脑区LKB1基因mRNA转录和p-LKB1蛋白表达的影响。将30只SD大鼠随机分成XFM组(M组)和生理盐水对照组(C组),M组又按照时间点的不同分为4个亚组。各组大鼠到达试验设计时间点后分别采取脑组织并分离各脑区,采用PCR和Western blot技术,分别检测各试验组中大鼠不同脑区LKB1基因mRNA的相对表达量和p-LKB1蛋白表达量。结果显示:在试验的麻醉早期阶段(即M1和M2),各脑区LKB1基因mRNA转录与对照组相比均未出现显著变化(P0.05);大脑皮层、海马及小脑p-LKB1蛋白表达与对照组比较并无显著变化(P0.05),而丘脑与脑干p-LKB1蛋白表达与对照组比较则明显升高,且丘脑差异显著(P0.05),脑干差异极显著(P0.01)。而在麻醉后期阶段(即M3和M4)各脑区LKB1基因mRNA转录表达明显上升,尤以M4突出,差异极显著(P0.01),其中丘脑和脑干变化最为明显;大脑皮层、海马及小脑p-LKB1蛋白表达与对照组比较均无明显变化(P0.05),但丘脑和脑干p-LKB1蛋白表达呈现显著升高(P0.05)。研究表明,XFM麻醉作用可能影响大鼠中枢神经系统中LKB1基因mRNA的转录和p-LKB1蛋白的表达。     

小型猪复合麻醉剂及其特异性颉颃剂交互作用对大鼠不同脑区iNOSmRNA转录的影响

为研究小型猪专用复合麻醉剂（XFM）及其特异性颉颃剂交互应用对大鼠不同脑区iNOS mRNA转录的影响,将48只SD大鼠随机分为生理盐水对照组（C）和XFM与颉颃剂交互作用组（MJ）,MJ组分为早期交互（MJ1、MJ2）和晚期交互（MJ3、MJ4）2个亚组。各组大鼠到达预定时间点后分别采取脑组织,应用实时荧光定量PCR技术检测各组织中iNOS mRNA表达量。结果显示,XFM及其特异性颉颃剂交互应用时,大脑、小脑、海马、脑干和丘脑中iNOS mRNA转录均受到显著抑制（P〈0.01）,虽能逐渐回升,但在试验选取时间点内只有小脑与海马中iNOS mRNA转录恢复正常。结果表明,XFM及其特异性颉颃剂在交互作用时能够显著抑制中枢神经系统中iNOS mRNA的转录,部分脑区可以完全恢复,这可能与XFM及其特异性颉颃剂交互作用机制有关。     

噻拉嗪对大鼠不同脑区DA及NE含量的影响

为研究噻拉嗪对大鼠不同脑区兴奋性单胺类神经递质含量的影响,探讨噻拉嗪的中枢麻醉作用机制。将32只大鼠随机分成4组(对照组、麻醉组、恢复Ⅰ组和恢复Ⅱ组)。用HPLC-荧光检测法测定各脑区去甲肾上腺素(NE)和多巴胺(DA)含量。结果显示,腹腔注射60 mg/kg体重噻拉嗪后,麻醉组大脑、小脑、脑干、丘脑、海马内NE含量降低,差异显著(P<0.05),其中大脑、丘脑、海马内DA含量降至最低,且差异显著(P<0.05);小脑、脑干内DA含量变化不明显,差异不显著(P>0.05)。表明大脑、小脑、脑干、丘脑、海马内NE含量和大脑、丘脑、海马内DA含量的降低,可能是噻拉嗪产生全麻作用的重要机理之一。     

噻环乙胺对大鼠不同脑区内源性阿片肽含量的影响

研究噻环乙胺麻醉下大鼠不同脑区内源性阿片肽含量的变化,探讨噻环乙胺中枢麻醉作用可能的机理。Wista大鼠128只,随机抽取8只为对照组,其余大鼠随机均分为5个试验组,分别用于测定L-Enk、M-Enk、β-EP、dynA和OFQ的含量;每个试验组又随机均分为麻醉组、恢复Ⅰ组和恢复Ⅱ组3个亚组。采用酶联免疫吸附试验(ELISA)测定各脑区内源性阿片肽的含量。结果显示腹腔内注射噻环乙胺25mg·kg-1后,麻醉组大鼠大脑皮层和丘脑内L-Enk、M-Enk、β-EP和dynA含量均显著增加(P0.05或P0.01),OFQ的含量显著降低(P0.05或P0.01);海马内L-Enk、M-Enk和β-EP含量均显著增加(P0.05或P0.01),dynA和OFQ的含量均无显著变化;脑干内M-Enk、β-EP和dynA含量均显著增加(P0.05或P0.01),OFQ的含量显著降低(P0.05),L-Enk的含量无显著变化;恢复Ⅰ组和恢复Ⅱ组,上述各脑区内L-Enk、M-Enk、β-EP、dynA和OFQ的含量均恢复显著(P0.05);麻醉全过程中,小脑内5种内源性阿片肽的含量均无显著变化(P0.05)。结果提示噻环乙胺对不同脑区内源性阿片肽的影响,可能是其产生全麻作用的重要机理之一。噻环乙胺中枢麻醉作用,可能与增加大脑皮层和丘脑内L-Enk、M-Enk、β-EP和dynA,海马内L-Enk、M-Enk和β-EP和脑干内M-Enk、β-EP和dynA的含量,同时降低大脑皮层、丘脑和脑干内OFQ的含量有关。     

小型猪复合麻醉剂对大鼠不同脑区突触体Ca^2＋，Mg^2＋-ATP酶活性的影晌

探讨Ca2＋，Mg2＋-ATP酶与小型猪复合麻醉剂全麻作用的关系，以判断该酶是否为该制剂作用的靶位之一。选取84只SD大鼠，先随机抽取12只为对照组，其余随机均分为高剂量小型猪复合麻醉剂组（腹腔注射7．5mg／kg）和低剂量小型猪复合麻醉剂组（腹腔注射5mg／kg），每个剂量组又随机均分为麻醉组、恢复I组和恢复Ⅱ组等3个亚纽。对照组腹腔注射生理盐水10mL／kg，5min后断头取材；麻醉组、恢复I组和恢复Ⅱ组分别在翻正反射消失即刻、翻正反射恢复即刻和大鼠可直线爬行后断头取材，在生理盐水冰面上取脑，用4℃生理盐水将脑上的血迹冲洗干净，迅速分离双侧大脑皮层、海马、小脑、脑干、丘脑，立即液氮冷冻。制备脑粗突触体，采用比色法测定ca2＋，Mg2-ATP酶活性。结果表明，小型猪复合麻醉剂的全麻作用与抑制小脑和丘脑突触体Ca2＋，Mg2＋-ATP酶活性相关，此酶可能是小型猪复合麻醉剂全麻作用的靶位之一。     

赛拉唑对大鼠不同脑区NO-NOS-cGMP信号转导系统的影响

观察赛拉唑对大鼠不同脑区NOS活性、NO和cGMP含量的影响,以探讨NO-NOS-cGMP信号转导系统对赛拉唑全麻分子机理的调控.Wistar纯种大鼠84只,随机选取12只为生理盐水对照组,其余随机均分为低剂量赛拉唑用药组和高剂量赛拉唑用药组,每个剂量组又分为麻醉期、翻正反射恢复期和苏醒期3个亚组(各12只).用分光光度法测定大鼠不同脑区NOS活性和NO产量,放射免疫法测定脑cGMP含量.结果表明,赛拉唑能明显地抑制大鼠大脑皮质、小脑、海马和脑干NOS活性、NO和cGMP含量.并且NOS活性、NO含量的抑制作用呈现荆量依赖性增加趋势,这种变化与大鼠赛拉唑麻醉后行为学变化相吻合.结果提示,NO-NOS-cGMP信号传递系统参与了赛拉唑全麻作用产生的分子学机制的调控.     

Parvovirus-induced encephalitis in a juvenile raccoon

A juvenile raccoon was euthanized because of severe neurologic signs. At postmortem examination, no significant gross lesions were present. Histologic evaluation demonstrated nonsuppurative encephalitis in thalamus, brainstem, and hippocampus, cerebellar Purkinje cell loss, as well as poliomyelitis and demyelination of the spinal cord. Parvovirus antigen–specific immunohistochemistry revealed immunopositive neurons in the brainstem, cerebral cortex, and hippocampus. A few Purkinje cells were also immunopositive. DNA extracted from formalin-fixed, paraffin-embedded brain tissue (thalamus, hippocampus, cerebral cortex) yielded a positive signal using PCR targeting both feline and canine parvovirus. Sequencing analyses from a fragment of the NS1 gene and a portion of the VP2 gene confirmed the presence of DNA of a recent canine parvovirus variant (CPV-2a–like virus) in the cerebellum. Our case provides evidence that a recent canine parvovirus (CPV) strain (Carnivore protoparvovirus 1) can infect cerebral and diencephalic neurons and cause encephalitis in an otherwise healthy raccoon. Parvovirus-induced encephalitis is a differential diagnosis of rabies and canine distemper in raccoons with neurologic signs.     

The histopathogenesis of paralytic rabies in six-week-old C57BL/6J mice following inoculation of the CVS-11 strain into the right triceps surae muscle

A fatal encephalomyelitis was developed after intracerebral and hind limb inoculation of in 6-week-old C57BL/6J mice by the inoculation of fixed rabies virus (CVS-11 strain), intracerebrally and into hind. After the intracerebral inoculation, virus antigens were detected in the cerebral cortex and hippocampus at 2 days postinoculation (PI), and later spread centrifugally to thalamus, brain stem, cerebellum, spinal cord and spinal ganglia. At 4 days PI, severe apoptosis and DNA fragmentation were observed in the hippocampus and cerebral cortex. All mice infected intracerebrally were dead without limb paralysis at from 10 to 11 days PI. In contrast, mice infected with virus intramuscularly were persistently observed virus antigens in the myocytes at the site of inoculation from 2 days PI. At 4 days PI, the antigens were demonstrated in the spinal dorsal root ganglia, spinal cord and muscle spindles without their detection in the cerebrum and hippocampus. There were no apoptosis in the spinal cord and dorsal root ganglia, however hind limb paralysis was found in all infected mice. Hind limb paralysis was progressed to quadriparalysis, and mice were dead from 11 to 13 days PI. From 4 days PI, necrosis of neuron was observed in the the spinal and dorsal ganglia with infiltration of lymphocyte. This study suggested that the necrosis of spinal neurons was more important to cause the paralysis of hind limb rather than the severe cerebral infection and apoptosis in C57BL/6J mice infected with CVS-11 strain. The virus primarily replicated in the muscles was ascended the spinal cord via afferent fibers and retrogradely invaded the cerebrum, and with subsequent spread to muscle spindles.     

An immunohistochemical and ultrastructural study on age-related astrocytic gliosis in the central nervous system of dogs.

The pattern of astrocytic gliosis (AG) was examined in 2-month-old to 18-year-old dogs using glial fibrillary acidic protein (GFAP) immunohistochemistry and electron microscopy. Coronal sections from various levels of the central nervous system (CNS) were stained with hematoxylin & eosin, Luxol Fast Blue, Nissl, and Bodian in addition to GFAP. A consistent pattern of age-related AG was observed in the dogs. The white matter, cortico-medullary junction, and subcortical nuclei in the cerebrum, central nuclei in the cerebellum, various nuclei in the brain stem, and grey matter of the spinal cord showed even and intense GFAP staining. AG was also prominent in the cerebral and cerebellar cortices and thalamus. Moderate AG was observed in the hippocampus and white matter of the cerebellum and spinal cord. Electron microscopy demonstrated increased number of profiles of degenerative neural components in the vicinity of hypertrophic astrocytes in the cerebral cortex of the aged dogs. Moderate to severe AG was consistently shown in the CNS of the aged dogs. In contrast, young normal dogs showed minimum amounts of GFAP-positive astrocytes in the CNS. These findings suggest that the observed AG in the CNS of the dogs is a morphological expression of aging.     

Natural scrapie: detection of fibrils in extracts from the central nervous system of sheep

Extracts from the cervical spinal cord and from the medulla, thalamus, cerebellum and cerebral cortex of the brains of 10 sheep, histopathologically confirmed as cases of scrapie, were examined by electron microscopy for the presence of scrapie-associated fibrils. Characteristic fibrils were observed in all the extracts except for that from the thalamus of one sheep. No fibrils were found in any extracts from three control sheep. A comparison of these results with a similar study of 22 cases of bovine spongiform encephalopathy (BSE) suggests that in cases of scrapie the area of the brain chosen for the detection of fibrils is less critical than in cases of BSE, in which fibrils are more readily extracted from areas of the brain stem.     

Immunolocalization of aquaporins in rat brain

The aquaporins (AQPs) are a family of homologous water channels expressed in many tissues. In this study, the expression and immunolocalization of different AQP subtypes in rat brains were investigated by RT-PCR, immunohistochemistry and immunofluorescence. The data showed that AQP1 was expressed in the subpial processes of astrocytes, choroid plexus and ependyma. AQP3, AQP5 and AQP8 had similar distribution patterns in piriform cortex, choroid plexus, hippocampus and dorsal thalamus. AQP4 and AQP9 were widely expressed in the rat brain and distributed in the subpial processes of astrocytes, ependyma, dorsal thalamus, hippocampus, white matter, suprachiasmatic nucleus (SCN) and supraoptic nucleus. AQP3, AQP4, AQP5, AQP8 and AQP9 were found in the Bergmann glial cells of cerebellum, cochlear nucleus and trapezoid nuclei. The distinct localization of various AQPs in cerebrum and the similarities of distribution patterns within cerebellum, cochlear nucleus and trapezoid nuclei suggest that AQPs may play an important role in maintaining the specific microenvironments of the brain.