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1.
电刺激下丘脑穹窿周围区(PFA)的下丘脑背内侧核(DMH),下丘脑腹内侧核(VMH)与下丘脑外侧区(LHA)均可引起心肌P0_2下降与血压升高,而以DMH所致的心肌P0,下降最明显(P<0.01)。心得安可取消电刺激LHA所致的心肌PO_2下降,部分取消电刺激VMH引起的心肌PO_2下降,而不改变电刺激DMH所致的心肌PO_2下降(P>0.05)。DMH、VMH微量注射谷氨酸钠(0.1mol/L0.5μl)均可诱发升压反应和ECG-ST压低,而LHA微量注射谷氨酸却导致降压反应,对ECG-ST无明显影响。上述结果提示DMH为PFA各区诱发心肌缺血缺氧的主要核团。兴奋DMH、VMH所致的心血管效应主要由胞体兴奋诱发,而电刺激LHA所致的升压反应主要为兴奋过路纤维引起,该区胞体兴奋主要导致降压反应。  相似文献   

2.
半导体激光针对中枢及外周内阿片肽神经递质的影响   总被引:3,自引:0,他引:3  
本工作应用半导体激光650nm 10mW CW照射“扶突”穴,发现L-ENK除在尾核区有非常显著的增加外,而在海马,丘脑,下丘脑则都有不同程度的下降,其显著性P值分别为P〈0.05,P〈0;01,P〈0.01。在外周血浆中L-ENK则亦有显著的增加。  相似文献   

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实验在氯醛糖麻醉、去缓冲神经、用三碘季铵酚麻痹和人工呼吸的86只猫身上进行。应用自功率谱(autosperum)和相干分析法(coherence analysis)证实了大脑额-项叶电活动(EEG)和心下交感神经冲动(SND)之间明显相关(34/44例)。SND活动落后于EEG50±20ms,互相关值(cross-correlation value)为0.4±0.1,相干值为0.25±0.05,均有显著的统计学意义。去大脑(A_3平面)使SND(3-4.2Hz频带)的功率明显下降的同时BP下降(5.47±0.13kPa),但EEG的总功率却保持不变,只是它与SND之间不再存在相关关系。在1h内SND节律和BP逐渐恢复。如果事先损伤下丘脑外侧部或中央丘脑,则上述去大脑的现象大大减弱。实验结果表明:猫前脑通过间脑有关的结构下传冲动调节和设置了交感神经活动的水平,一旦这种联系被阻断,脑干有关的心血管中枢就会代偿性维持交感神经活动。  相似文献   

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目前已知下丘脑是应激反应的关键性调节中枢,下丘脑内一氧化氮是否参与应激反应尚未见报道。本文运用NADPH-d酶组化技术和计算机图象分析方法,对束缚应激大鼠下丘脑室旁核(PVN)和视上核(SON)一氧化氮合酶(NOS)阳性神经元的相对切面面积和平均灰度进行了分析。结果显示,大鼠在急性束缚应激4小时后,其下丘脑PVN和SON内的NOS阳性神经元的平均灰度值与正常大鼠比较均明显降低(P<0.001);SON的NOS阳性神经元的相对切面面积明显大于正常大鼠(P<0.001),但PVN的NOS阳性神经元的相对切面面积未见明显改变(P>0.05)。以上结果说明束缚应激使大鼠下丘脑PVN和SON的NOS活性增强  相似文献   

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动情周期中大鼠输卵管上皮凝集素受体的研究   总被引:3,自引:0,他引:3  
大鼠动情周期包括动情前期(PE)、动情期(E)、动脉后期(ME)和动情间期(DE)。采用生物素标记的5种凝集素(ConA、PNA、RCA、UEA-I以及WGA)对大鼠动情周期中输卵管上皮细胞的凝集素受体进行了研究,发现在大鼠动情周期中输卵管粘膜上皮细胞凝集素受体均有不同程度的变化:其中,ConA的阳性反应以PE组最强,DE组最弱(P<0.01);PNA的阳性反应以E组最强,DE组为阴性;RCA的阳性反应强度以PE和E组最强,DE组最弱(P<0.01);UEA-Ⅰ的阳性反应颗粒可见于动情周期各期,但以PE组为强(P<0.01),其它各期间的反应强度差异无显著性(P>0.05);WGA的阳性反应以DE组最强,与其它各组比较,差异有高度显著性(P<0.01),其它各组之间阳性反应强度差异无显著性(P>0.05)。说明输卵管上皮细胞的糖组分在动情周期中发生了某些变化。推测这些变化有利于输卵管功能活动的进行  相似文献   

6.
杜继曾  吴雁 《兽类学报》1997,17(3):204-207
用脑室注射神经递质去甲肾上腺素(NE)和RIA法测定下丘脑正中隆起处促肾上腺皮质激素释放激素(CRF)水平,研究NE对高原鼠兔下丘脑CRF分泌的作用。脑室给予不同剂量NE3.75,7.5,15,30μg/100gBW.正中隆起(ME)处CRF含量分别增加到对照组的106.05%,135.28%(P<0.05),138.94%(P<0.01),103.65%,同时,血浆皮质酮浓度也分别增加到对照组的323.35%(P<0.01),323.35%(P<0.001),346.71%,366.47%。肾上腺切除后2天和6天时,下丘脑NE下降到对照的76.32%(P<0.05),76.27%(P<0.01),血浆皮质酮也下降到16.57%(P<0.01),2.05%(P<0.001)。上述结果表明,NE刺激高原鼠兔下丘脑CRF的分泌并激活下丘脑垂体肾上腺皮质轴。肾上腺皮质激素对维持下丘脑NE水平和CRF神经元活动有一定的紧张作用  相似文献   

7.
应激引起血压升高大鼠血管升压素V1受体mRNA水平改变   总被引:10,自引:1,他引:9  
Lu LM  Wang J  Yao T 《生理学报》1999,51(4):471-476
实验在雄性SpragueDawley 大鼠上进行。实验动物被随机分为对照组和应激组, 应激组大鼠每天给予电击足底结合噪声的应激刺激, 每日2 次, 每次2 h 。应激组大鼠在接受连续15 d 的慢性应激刺激后, 其尾动脉收缩压与对照动物相比有显著升高。对照组为16-25 ±0-63kPa (n = 7) ; 应激组为19-55 ±1-45 kPa (n = 8, P< 0-05) 。用RTPCR 结合Southern 印迹核酸分子杂交技术观察到, 血管升压素(vasopressin, AVP)V1 受体mRNA 广泛存在于大鼠下丘脑、皮质、延髓等部位以及心脏、肝脏、肾脏等组织中。用定量PCR 方法观察到, 大鼠在接受慢性应激刺激之后, 其大脑顶叶皮质、下丘脑及延髓组织中AVPV1 受体mRNA 水平均显著低于正常大鼠( 顶叶皮质: P< 0-05 ; 下丘脑: P< 0-01 ; 延髓: P< 0-001) , 而心脏、肝脏及肾脏组织中的AVPV1 受体mRNA水平与正常大鼠相比均无明显差别( 心脏: P> 0-05 ; 肝脏: P> 0-05 ; 肾脏:P> 0-05) 。上述结果提示, 慢性应激刺激可引起大鼠不同部位脑组织AVPV1 受体合成水平下调, 可能导致  相似文献   

8.
为探讨脑内心房钠尿肽(ANP)的作用,本工作采用SD大鼠,用放射免疫方法测定3/4肾大部切除与高盐摄食后脑内ANP的含量。结果表明,对照组大鼠脑内ANP分布广泛。3/4肾切除大鼠每日饮水量,尿量均比对照组高(P<0.05),尿钠浓度低于对照组时,脑内ANP含量尽管略有增加,但10个核团(下丘脑室周核、弓状核、室旁核、视前室周核、中缝背核、尾壳核、杏仁核、脑桥背侧部、蓝斑和大脑皮质)ANP含量和对照组无明显差别(P>0.05)。高盐摄食组每日饮水量和尿量均比对照组高,且尿钠浓度高于对照组,同时下丘脑室周核和弓状核ANP含量比对照组高(P<0.05)。上述结果提示,大脑第三脑室前腹侧区(AV3V区)的ANP可能在水盐调节上发挥重要作用。  相似文献   

9.
电磁脉冲对大鼠学习和脑内神经递质的影响   总被引:9,自引:0,他引:9  
探讨电磁脉冲(EMP)对大鼠神经系统的效应。实验采用Wistar大鼠,EMP辐照后不同时间用Y-型迷宫测其学习能力,高效液相色谱法检测脑不同部位的神经递质含量。与假照射组(对照组)相比,照后三天内各测定组大鼠学习能力降低(P<0.05),其中照射后第1天组的海马内5-羟色胺(5-HT)和多巴酸(DOPAC)含量升高(P<0.05),下丘脑多巴胺(Dopamine)含量升高(P<0.05),肾上腺素(Adr)含量降低;照后2天组海马Adr含量降低(P<0.05),海马5-HT含量升高(P<0.05);照后3天组海马内Adr含量降低(P<0.05)。EMP能够改变大鼠不同脑区神经递质的含量,降低大鼠学习能力  相似文献   

10.
利用抗体免疫沉淀技术研究了血管紧张素II,δ受体激动剂和k受体激动剂对大鼠脑组织c-fos原癌基因表达的影响,结果表明,0.1μmol/L AⅡ可显著刺激脑组织中Fos蛋白的表达,0.1μmol/LDPDPE和0.1μmol/L NDAP对Fos蛋白的表达亦有一定的诱导作用。AII与DPDPE或NDAP共同处理组织,Fos蛋白表达水平低于AII单独诱导的水平,结果表明阿片肽可抑制AII对Fos蛋白  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

16.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

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Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

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