北京鸭下行投射到脊髓的神经元在脑内的分布——用HRP逆行追踪法研究

用HRP法,逆行追踪了54例北京鸭下行投射到脊髓的神经纤维的起始部位。用乌拉坦麻醉,分别在脊髓的C_7、颈膨大或腰膨大部注射30～50％HRP,灌流固定,取脑做冰冻连续切片。蓝色反应显色,中性红复染,镜检。实验结果,各脑区出现的标记细胞主要位于同侧,对侧较少。而红核内的标记细胞绝大多数分布于对侧,同侧极少。在其它部位,同侧前庭外侧核中,标记细胞较多,双侧的前庭内侧核和对侧的前庭降核中标记细胞极少。对侧小脑内侧核中有较多的标记细胞,对侧小脑皮质的蒲金野细胞层也有少量标记细胞。脑桥和延髓的外侧网状核、巨细胞网状核及延髓中央核均有标记细胞。中缝核有大量标记细胞。另外,下丘脑室旁核及其腹侧和腹外侧的内细胞层和外细胞层,也有标记。在迷走背核、疑核、孤束核、蓝斑及蓝斑下核都有直接到脊髓的投射。在大脑各部和中脑顶盖内未见到标记细胞。本文结合哺乳类和某些禽类的资料与北京鸭的下行传导通路的起源进行了比较。结果表明:北京鸭具有与哺乳类相似的红核脊髓束、前庭脊髓束、网状脊髓束、小脑脊髓束、中缝脊髓束及孤束核脊髓束,而没有大脑皮质脊髓束和顶盖脊髓束。本文中的发现,迷走背核、疑核和小脑皮质向脊髓的直接投射,尚未见过报道。     

雏鸡脑雌激素受体的表达及分布

采用免疫组化SP法研究了雌激素受体在lO日龄雏鸡脑组织内的表达，着重观察了雌激素受体在小脑、中脑、下丘脑及端脑的分布。研究表明，雌激素受体主要存在于细胞核中，少数区域仅存于胞浆或胞膜。雌激素受体在脑内分布广泛。在小脑中部皮质的颗粒层、蒲肯野氏层，中脑的中央白质、外侧丘系腹侧核、视束、后连合等区域，雌激素受体免疫反应产物为高密度；在小脑前部皮质的颗粒层，中脑中央灰质、尾侧线形核，端脑副高纹状体等区域，雌激素受体免疫反应产物为中等密度；小脑前部皮质的蒲肯野氏细胞，下丘脑视上核，端脑原始旧纹状体等区域，雌激素受体免疫反应产物为低密度。结果揭示，在鸡脑早期发育过程中，雌激素起著广泛而重要的作用。     

鸡端脑向小脑投射的起始核

将40%辣根过氧化物酶（HRP）水溶液注入鸡小脑的Ⅵ、Ⅶ、Ⅷ叶，逆行追踪其端脑向小脑投射的起始核。结果发现，端脑的海马列、隔核、带核、旁嗅叶出现多量标记细胞；副高纹状体、嗅结节和古纹状体出现少量标记细胞。将CB-HRP引入古纹状体，于小脑皮层的分子层内出现顺行标记物，颗粒层内也有稀疏的顺行标记物出现。结果表明，鸡端脑-小脑投射的起源较为丰富而广泛，上世纪初提出的纹-小脑束可能起始于古纹状和带核。     

鸡上纹状体的纤维联系——HRP法研究

将HRP溶液注入鸡上纹状体,追踪投射至上纹状体的纤维来源,在丘脑背外侧前核、背外侧后核,丘脑背内侧前核、背内侧后核,中脑深核外侧部和腹侧部及顶盖背核出现标记细胞。外侧前脑束和隔中脑束出现标记纤维。结果表示.上述核团有纤维投射到上纹状体,且投射均限于同侧。     

仔猪下丘脑内生长抑素mRNA的分布定位——原位杂交组织化学法研究

用原位杂交组织化学法研究了５只仔猪下丘脑内生长抑素ｍＲＮＡ的分布。结果表明，生长抑素ｚｎＲＮＡ主要见于下丘脑腹内侧核、穹窿周核、腹外侧核、弓状核、室旁核和室周核，此外在视交叉上核、视上核、下丘脑前区和后区偶见零散标记细胞。本研究结果与在绵羊和豪猪上用免疫组织化学法获得的结果略有不同，除与研究方法和种属差异有关外，还可能与实验动物年龄有关。     

IFN-γR和ER在大鼠下丘脑中的共存

为了探讨神经-免疫-内分泌网络中生物活性物质间相互调节和平衡的关系,本试验应用免疫组化双标记法对成年SD雌性大鼠下丘脑中IFN-γ受体（IFN-γR）和雌激素受体（ER）的共表达进行了研究。结果发现,IFN-γR和ER广泛存在于大鼠下丘脑中,其中在视前交叉上核、视前内侧核、室周核、交叉上核、下丘脑前核、下丘脑内侧核、下丘脑外侧核、乳头体前背侧核、乳头体前腹侧核等13个核团中存在大量的IFN-γR和ER双标记细胞,双标记细胞约占全部阳性标记细胞的60．9％;双标记细胞胞质呈黑褐色、胞核呈棕黄色;ER单标着色细胞以神经胶质细胞居多。研究结果表明,IFN-γ和雌激素可以分别以其各自受体为介质进行信号传递和信息整合,同时也通过在同一细胞中的相互作用而参与机体的神经-免疫-内分泌调节。     

北京鸭迷走背核向脊髓的直接投射——HRP法研究

采用HRP逆行追踪法,对25例北京鸭迷走背核直接投射到脊髓的传导通路的起始部位进行了研究。乌拉坦(Urethane)静脉注射麻醉动物,分别在脊髓的颈中部(C7)、颈膨大部和腰膨大部注时30～50％HRP,灌流固定,取脑做冰冻连续切片,蓝色反应显色,中性红复染,镜检。实验结果:单侧脊髓注射HRP后,在延髓的闩后部分,双侧的迷走背核内发现了标记细胞,对侧的标记细胞数量多于同侧。此外,双侧的疑核和孤束核也有一些标记细胞。在颈中部脊髓引入HRP后,出现的标记细胞较多;在颈膨大部引入HRP后,出现的标记细胞较少;在腰膨大部引入HRP后,迷走背核内不出现标记细胞,而疑核和孤束核仍有少量标记细胞。本文对禽类迷走背核和疑核至脊髓的直接传导通路,结合哺乳类的有关资料进行了讨论。     

北京鸭中缝脊髓束的起源和细胞构筑——HRP逆行追踪法研究

北京鸭60例,分别在其脊髓一侧的外侧索、腹侧索或灰质中引入HRP,冰冻切片,蓝色反应法显色,中性红复染.结果发现,从延髓到脑桥这一范围的中缝核群内,出现了大量的标记细胞,而在脑桥吻侧以上的中缝核内出现的标记细胞很少.研究结果表明:北京鸭存在着比较发达的中缝脊髓下行传导通路,它主要起始于中缝大核、中缝隐核和中缝苍白核,而这一通路是位于脊髓的外侧索与腹侧索.     

禽类下丘脑室旁核向脊髓的直接投射

用微电泳和微量进样技术将ＨＲＰ引入麻鸭、鹅、鸡、鸽子和鹌鹑脊髓的颈中部、颈膨大和腰膨大一侧灰质中，冰冻切片，ＢＤＨＣ法显色，中性红复染。结果，５种动物下丘脑的双侧室旁核内均发现大量标记细胞；同侧标记细胞数多于对侧；标记细胞密集于第３脑室两侧壁的背外侧，形态多为圆形或椭圆形，胞体直径为２０～３５μｍ。本研究结果表明，禽类下丘脑的室旁核可向脊髓发出直接投射，这一直接传导通路呈双侧性投射，但以向同侧脊髓投射占优势，该通路投射的范围广泛分布于脊髓的颈、胸、腰段。     

鸡视顶盖后背侧部的纤维联系——HRP法研究

选用健康成年来航鸡9只,以20～30％HRP溶液作标记物,观察了视顶盖后背侧部的神经纤维联系。结果:在光镜下明视野视察,标记细胞出现在古纹状体后腹部、外侧螺旋核、视上交叉腹侧核、顶盖前核、峡核大细胞部和深中脑外侧核,在内侧螺旋核和视顶盖中央灰层偶见标记细胞;在腹外侧膝状体核、圆核、顶盖前顶盖下间置核、背外侧膝状体核、前顶盖下核、丘脑背外侧核、视顶盖室周纤维层以及中脑和延髓的网状结构等部位观察到标记终枝;同时观察到顶盖丘脑束中有标记纤维的横断像以及视上腹侧交叉和顶盖连合中有标记纤维。结果表明,视顶盖的纤维比较广泛,与端脑、间脑、中脑以及延髓都有联系,视上腹交叉是两眼间视觉信息交流的形态学基础。     

Afferent and efferent connections of the nucleus geniculatus lateralis ventralis demonstrated by WGA-HRP in the chick

Fibre connections of the chick nucleus geniculatus lateralis ventralis (GLv) were investigated using the axonal tracing method with wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). After an injection of WGA-HRP into the GLv, many labelled neurons were observed in layer i of the stratum griseum et fibrosum superficiale (SGFS) in the ipsilateral tectum opticum (TO) and in the nucleus lentiformis mesencephali (LM). In the TO-GLv projection, cells of origin were located in the deeper part of layer i of the TO and were topographically distributed along the direction from the rostrodorsal part to the caudoventral part of the TO relating to a rostrocaudal axis of the GLv. In the LM-GLv connection, the dorsal and ventral parts of the LM connected reciprocally with the rostral and caudal halves of the GLv, respectively. In contrast, in the GLv efferent connection, labelled axon terminals spread widely in the ipsilateral area pretectalis without any clear topographical arrangement.     

Localisation of recurrent laryngeal nerve motoneurons in the sheep by means of retrograde fluorescent labelling

The purpose of this investigation was to determine the central distribution of the efferent neurons of the recurrent laryngeal nerve (RLN) in the sheep by the use of the retrograde transport of the fluorescent tracer Fast Blue. The distribution of the RLN neurons was also compared with that of the neurons simultaneously labelled by injection of another tracer, Diamidino Yellow dihydrochloride, into the cervical trunk of the vagus nerve (CTV). Injections of the tracer into the CTV resulted in heavy retrograde labelling of neurons in the ipsilateral dorsal motor nucleus of the vagus nerve, in the nucleus ambiguus, in the nucleus retroambigualis and in the reticular formation surrounding the nucleus ambiguus. Following injections of the tracer into the RLN, labelling of neurons was seen over a wide area of the ipsilateral nucleus ambiguus and in the nucleus retroambigualis. Species differences in the distribution of the efferent component of the RLN are discussed, in particular ruminants compared to nonruminants.     

Distribution of sympathetic and afferent neurones innervating the submandibular gland in the sheep

The distribution of sympathetic and sensory neurones innervating the submandibular gland (SMG) in sheep was studied using retrograde tracing technique. The retrograde tracer Fast Blue (FB) was unilaterally injected into the SMG in five juvenile male sheep under general anaesthesia. After a 4-week survival period, all the animals were reanaesthetized, perfused transcardially with 4% buffered paraformaldehyde and ganglia, which could be considered as a potential sources of sympathetic, and afferent innervation of the gland were bilaterally collected. The FB-labelled sympathetic neurones were found in the ipsilateral superior and middle cervical ganglion. Many labelled neurones were distributed in the ipsilateral jugular and nodose ganglia of the vagus nerve and smaller numbers of the nerve cells were also found in ipsilateral C1-C3 dorsal root ganglia (DRG). No labelled neurones were observed in the ipsilateral stellate ganglion, trigeminal ganglion, C4-C8 DRG and in all contralateral ganglia. The present study revealed that the majority of sympathetic neurones projecting to the sheep SMG are found in the superior cervical ganglion but some of them are also distributed in the middle cervical ganglion. Most of the afferent neurones are located in the jugular and nodose ganglia of vagus nerve but C1-C3 DRG also comprise some of these nerve cells.     

The milk-ejection reflex in the sheep: an anatomical study on the afferent pathway

The present study is an attempt to reveal the spinal and supra-spinal organization of the ascending branch of the milk-ejection reflex in the ewe by means of a tract-tracing technique. For this purpose, injections of horseradish peroxidase (HRP) were performed into the lateral cervical nucleus (LCN) and into the hypothalamic paraventricular nucleus (PVN). Peroxidase injections into the LCN revealed retrogradely labelled neurons in the medial part of laminae I–III of the ipsilateral L₃ and L₄ spinal segments, while injections of HRP into the PVN revealed retrogradely labelled cells in the contralateral LCN and the medial cuneate nucleus. Taking into account the results obtained, it is concluded that the transmission of the afferent input from the nipples to the PVN is accomplished by at least two pathways: one employing a single relay station located in the medial cuneate nucleus, and another possessing two relay stations located in the medial part of laminae I–III of the dorsal horn of L₃ and L₄ spinal segments and in the LCN.     

鸡脑光信息通路的对侧联系

目的:为了进一步阐明光照对鸡生产性能的神经调节机制,为养鸡生产科学利用光照和兽医神经外科学提供一定的理论依据,用HRP追踪技术对鸡脑光信息通路的对侧联系进行了观察。方法:用脑立体定位仪向鸡脑圆核注射微量3%WGA-HRP,存活30小时后灌流固定,取脑并制作冰冻切片,用TMB法检测鸡脑光信息通路中投射向对侧的HRP标记神经细胞。结果:将WGA-HRP注入圆核后,除在同侧鸡离顶盖光信息通路的中央灰质层(SGC)和SP/IPS核见有大量HRP标记神经细胞外,在对侧SGC、SP/IPS核和圆核也观察到了一些HRP标记神经细胞体和纤维,但其数量较少,分布范围小,在对侧圆核的不同部位HRP标记细胞和纤维分布位置不同,标记范围呈前后小中间大的纺锤状。讨论:结果表明鸡离顶盖光信息通路主要是同侧投射,也有部分对侧投射。对侧投射可能通过对同侧投射辅助和抑制作用来整合信息,使特定单元结合和处理来自双眼的信息,有助于大脑获得更加精确而全面的信息。     

鸡海马结构传入纤维的端脑起始核DiI法研究

研究鸡海马结构传入纤维在端脑内的起始核。采用DiI逆行追踪法,将DiI注入鸡端脑海马结构,逆行追踪投射到海马结构的起始核。结果在端脑的副高纹状体、内侧隔核、古纹状体、带核和后背外侧区出现标记神经元。初步表明端脑内的上述核团是向海马结构投射的起始核。     

Afferent and efferent connections of the nucleus rotundus demonstrated by WGA-HRP in the chick

Organization of the fibre connections in the chick nucleus rotundus (Rt) was investigated by an axonal tracing method using wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). After an injection of WGA-HRP into the Rt, labelled neurones were observed in the striatum griseum centrale (SGC) in both sides of the tectum (TO) and in the ipsilateral nucleus subpretectalis/nucleus interstito-pretecto-subpretectalis (SP/IPS). Labelled fibres and terminals were also found in the ipsilateral ectostriatum (Ect). These fibre connections were topographically organized rostrocaudally. In the TO-Rt projection, the rostral and the dorsocaudal parts of the Rt received afferents from the superficial part of the SGC, the middle part of the Rt received afferents from the intermediate part of the SGC, and the ventrocaudal part of the Rt received mainly fibres from the deep part of the SGC. These topographic projections were accompanied by a considerable number of diffuse projections to the thalamic regions surrounding the Rt. In addition, the rostral and middle caudal parts of the Rt received afferents from the lateral and medial parts of the SP/IPS, respectively, and respective parts of the Rt sent efferents to the lateral and medial parts of the Ect.     

Projections from the anterior interposed nucleus to the red nucleus diminish with age in the mouse

To analyse the effect of ageing on the projection of the anterior interposed nucleus to the red nucleus, we injected the retrograde tracer fluorogold in the red nucleus of 3-, 6- and 12-month-old mice. The number of labelled neurones in the anterior interposed nucleus fell by 9% between 3 and 6 months and by another 9% between 6 and 12 months (all P < 0.001). This suggests that loss of neurones from the cerebellar nuclei starts well before old age.