1、Histologic structure of nervous system,Spinal cord,The gray matter of the spinal cord ventral horns（前角） : somatic motor neurons multipolar neuron, (axon ventral root) neurons larger, 支配骨骼肌 neurons small，支配梭内肌 Ranshaw cells short axon，抑制 neurons,Lateral column （侧角）: multipolar neuron （节前神经元） axon 交感神
2、经节 （ 与节细胞建立突触） dorsal horns（后角） : small neurons， accept the impulse from dorsal root fibers（感觉神经元的中枢突） axon（上行纤维束 ） 脑干，小脑，丘脑 “tract cell”,2. The whiter matter of the spinal cord longitudinally arranged nerve fibers,Figure : Cross section of the spinal cord in the transition between gray matter (belo
3、w) and white matter (above). Note the neuronal bodies and abundant cell processes in the gray matter, whereas the white matter consists mainly of nerve fibers whose myelin sheath was dissolved by the histologic procedure. PT stain. Medium magnification.,Cerebral cortex,1.The types of neurons : pyram
4、idal cell （锥体细胞） granular cell （颗粒细胞） fusiform cell（梭形细胞）,Figure : Silver-stained section of cerebral cortex showing many pyramid-shaped neurons with their processes and a few glial cells. Medium magnification.,pyramidal cell: （大脑皮质的主要投射神经元） 主树突 皮质表面 轴突 脑干或脊髓（投射纤维） 同侧或对侧的皮质（联合纤维） 大，中锥体细胞 投射神经元 小锥体细胞
5、 中间神经元,granular cell：（大脑皮质的中间神经元） stellate cell（星形细胞）： short axon pyramidal cell or fusiform cell horizontal cell（水平细胞）： dendrites and axons parallel to the surface of cortex 锥体细胞顶树突 basket cell（篮状细胞）： fusiform cell：投射神经元 exist in inner cortex dendrites the surface of cortex axons medulla（投射纤维）,Six-
6、layered structure of cerebral cortex,Molecular layer: small neurons -horizontal cells and stellate cells few neurons, more nerve fibers which are parallel to the surface of cortex 2. External granular layer : many stellate cells and few small pyramidal cells,3. External pyramidal layer: thick many m
7、edium and small pyramidal cells many stellate cells,4. Internal granular layer: many stellate cells 5. Internal pyramidal layer: medium and large pyramidal cells,6. Polymorphic layer: fusiform cells some pyramidal cells and granular cells,N,Mi,Figure : Microglia. Silver stain. Paraffin section. x 54
8、0. This photomicrograph is of a section of the cerebral cortex, demonstrating the nuclei (N) of nerve cells as well as the presence of microglia (Mi). Note that microglia are very small and possess a dense nucleus (N) along with numerous cell processes (arrows).,Cortex vertical column（垂直柱）,皮质细胞纵向柱状排
9、列 贯穿皮质 可能是大脑皮质的基本功能单位,包括：传入纤维 传出神经元 中间神经元,Cerebellar cortex,1. Molecular layer 2. Purkinje cell layer 3. Granular layer,1. Molecular layer,Thick Few neurons- small stellate cells (outer molecular layer) basket cells (inner molecular layer) -long axon parallel to the surface of cerebellum,the end of
10、branches surround to the purkinje cells and form synapses,2. Purkinje cell layer,One layer : the body of purkinje cells 主树突 分子层 （侧柏叶状） 轴突 髓质（终止于小脑 内部核群）,3. Granular layer,granular cells : short dendrits axon（“T” shape） molecular layer parallell fibers（form synapses with purkinje cells） Golgi cells:
11、dendrits molecular layer ,connected to parallell fibers axons granular layer , connected to granular cells,Figure :Photomicrograph of the cerebellum. The staining procedure used (H&E) does not reveal the unusually large dendritic arborization of the Purkinje cell. Low magnification.,Figure : Cerebel
12、lum. Human. Paraffin section. x 132. The granular layer (GL) is composed of closely packed granule cells (GC). The Purkinje cells (PC) send their axons into the granular layer, while their dendrites arborize in the molecular layer (ML). This layer also contains unmyelinated fibers from the granular
13、layer as well as two types of cells, basket cells (BC) and the more superficially located stellate cells (SC).,GC,PC,GL,ML,BC,SC,Figure :Purkinje cell. Human cerebellum. Paraffin section. x 540. This is a higher magnification of the boxed area of Figure x. The granular layer (GL) of the cerebellum i
14、s composed of two cell types, the smaller granule cells (GC) and larger Golgi type II cells (G2). The flask-shaped Purkinje cell (PC) displays its large nucleus (N) and dendritic tree (D). Nuclei of numerous basket cells (BC) of the molecular layer (ML), as well as the unmyelinated fibers (UF) of th
15、e granule cells, are well defined in this photomicrograph. These fibers make synaptic contact (arrows) with the dendritic processes of the Purkinje cells.,UF,D,N,PC,BC,ML,GC,GL,G2,Figure : Section of the cerebellum with distinct Purkinje cells. One Purkinje cell shows part of its rich dendritic arbo
16、rization. H&E stain. Medium magnification.,Ganglia,Cerebrospinal ganglia (脊神经后根，某些脑神经干上）,Figure: Silver-impregnated sensory ganglion consisting of pseudounipolar neurons. Medium magnification.,sensory ganglia nerve fibers arranged parallelly（myelinated nerve fiber） many pseudounipolar neurons 卫星细胞包裹
17、着节细胞胞体及其盘曲的突起,有髓神经纤维,Figure : Sensory ganglion. l.s. Human. Paraffin section. x 132. The dorsal root ganglion provides a good representative example of a sensory ganglion. It possesses a vascular (BV) connective tissue capsule (C) that also envelops its sensory root. The neurons of the dorsal root g
18、anglion are pseudounipolar in morphology; therefore, their somata (So) appear spherical in shape. The fibers (f), many of which are myelinated. Note that some somata are large ( arrow ) while others are small ( arrowhead ). Each soma is surrounded by capsule cells (Cc).,BV,C,So,Cc,f,Figure : The sph
19、erical cell bodies display their centrally located nuclei (N) and nucleoli (n). Observe that both small ( arrowheads ) and large ( arrows ) somata are present in the field, and that the nuclei are not always in the plane of section. Hematoxylin and eosin stains the somata a more or less homogeneous
20、pink, so that organelles such as Nissl substance are not visible. However, the nuclei and cytoplasm of capsule cells (Cc) are clearly evident. Moreover, the small, elongated, densely staining nuclei of fibroblasts (F) are also noted to surround somata, just peripheral to the capsule cells.,Cc,F,N,n,
21、2. Autonomic ganglia,节细胞：自主神经系统的节后神经元，多极的运动神经元。 核常偏位。 卫星细胞数量少，不完全包裹节细胞胞体。 神经纤维：多为无髓神经纤维（节前纤维和节后纤维），分散。,内脏及血管的平滑肌，心肌和腺上皮细胞（内脏运动神经末梢）,节细胞的树突，胞体,（交感神经节和副交感神经节）,sympathetic ganglion：交感神经节,more principal ganglion cell（主节细胞）： 多属于肾上腺素能神经元，少数为胆碱能神经元 few small intensely fluorescene cell（小强荧光细胞）： 聚集成群，荧光组织化学
22、强荧光 释放多巴胺，轴突 主节细胞 （可能是中间神经元）,Figure :Sympathetic ganglion. l.s. Paraffin section. x 132. These ganglia are enveloped by a collagenous connective tissue capsule (C) that sends septa (S) containing blood vessels (BV) within the substance of the ganglion. The arrangement of the cell bodies of the multi
23、polar neurons (MN) within the ganglion appears to be haphazard. This very vascular structure contains numerous nuclei that belong to endothelial cells (E), intravascular leukocytes (L), fibroblasts (F), and those of the supporting cells (SS) surrounding the nerve cell bodies.,C,BV,E,S,MN,L,F,Ss,Figu
24、re :Sympathetic ganglion. l.s. Paraffin section. x 540. Although neurons of the sympathetic ganglion are multipolar, their processes are not evident in this specimen stained with hematoxylin and eosin. The nucleus (N) with its prominent nucleolus (n) is clearly visible. The cytoplasm contains lipofu
25、scin (Li), a yellowish pigment that is usually seen in neurons of older individuals. The clear space between the soma and the supporting cells (SS) is a shrinkage artifact. Note the numerous blood vessels (BV) containing red blood cells (arrows) and a neutrophil (Ne).,N,n,Li,Ss,Ne,BV,BV,Cerebrospina
26、l meninges,dura mater (硬膜）： dense connective tissue subdural space (硬膜下隙） arachnoid（蛛网膜）: thin connective tissue subarachnoid space （蛛网膜下隙）fibers form trabeculae connecte to pia mater（蛛网膜结构），contain cerebrospinal fluid pia mater（软膜）: thin connective tissue，rich in blood vessels,Choroid plexus and ce
27、rebrospinal fluid,脉络丛：第三，四脑室顶和部分侧脑室壁。,组成：由富含血管的软膜与室管膜直接相贴并突入脑室而成的皱襞状结构。 室管膜 脉络丛上皮,分泌脑脊液,cerebrospinal fluid： （脑室，脊髓中央管，蛛网膜下隙和血管周隙） few protein rich in Na，K，CL nourish and protect brain and spinal cord,脑脊液循环：脉络丛上皮不断分泌脑脊液，又不断回流入血液（通过蛛网膜粒）,蛛网膜突入颅静脉窦内的绒毛状突起,Blood-brain barrier,bloodcerebrospinal fluid barrier,Cerebrospinal fluid-brain barrier,软膜 胶质膜 脑室的室管膜,Function： 选择性阻止某些物质 由脑脊液进入脑组织。,脉络丛上皮, 脉络丛毛细血管内皮 Function：保持脑脊液稳定的成分而不同于血液。,
