CNS Sequence CNS Histology March 10, 2008 S.K. Kim / J.M. Velkey

Spinal cord & peripheral ganglia Dorsal horns: Interneurons Ventral horns: Somatic motor neurons Lateral horns: Sympathetic visceral motor neurons Parasympathetic (S2-4) VM neurons DRG: Sensory (pseudounipolar) neurons Autonomic ganglia: Post ganglionic neurons with unmyelinated axons. Sympathetic: paravertebral & preaortic (celiac, superior mesenteric, etc.) ganglia Parasympathetic: in organ walls

#65 Spinal cord and DRG Ventral horn Lateral horn Dorsal horn Dorsal root ganglion (DRG)

Motor neurons, glial cells and neuropil Glial cells Neuropil

Dorsal root ganglion

Motor and Sensory Neurons (Multipolar) (Pseudounipolar)

DH DC VH LH DH = dorsal horn DC = dorsal nucleus of Clarke - thoracic spinal cord LH = lateral horn VH = ventral horn

66a Spinal Cord (ventral horn motor neurons)

Thoracic cord lateral horn: preganglionic sympathetic neurons of intermediolateral cell column

Thoracic cord lateral horn: spinocerebellar neurons of Clarke’s nucleus (relay proprioceptive input up to cerebellar cortex: e.g. from muscle spindle  DRG  spinocerebellar neuron  cerebellum)

Thoracic cord: dorsal horn neurons (interneurons) short projections to other neurons at same level or nearby spinal level

Cerebrum Sulcus (sulci) Gyrus (gyri) Cerebellum PonsMedulla oblongata 3 rd ventricle 4 th ventricle Brain

Cerebrum and Cerebellum

Cerebellum Cerebrum W W C C C M C: Cortex of gray matter W: White matter W/M = White matter of cerebellum also called “medulla”

#77 Cerebellum Cortex White matter

Slide 77a – luxol blue white matter cortex (gray matter)

#77 Cerebellum WM GL ML PC

#76b Cerebrum – tol. blue & eosin

#76 Ross and Pawlina, p.311 Cerebral cortex

Layer III pyramidal cells Layer V pyramidal cells

#NP004N Hippocampal region CA: Cornus ammonis CA1 CA3 CA2 Dentate gyrus HippocampusCA4 (hilus) choroid plexus “typical” ependymal cells (columnar, lining cells) ependymal cells of choroid plexus (cuboidal, eosinophilic: produce CSF)

3 layers of Hippocampal region (CA1-CA3) Molecular layer Pyramidal cell layer Polymorphic layer Pyramidal cells

3 layers of Dentate gyrus Molecular layer Granule cell layer (neurons) Polymorphic layer Polymorphic layer (interneurons and granule cell axons) Molecular layer (dendrites of granule cells)

Cerebellum – H&E Cerebrum – TB&E C C W W Purkinje cells (neurons) Layer V Pyramidal cells (neurons) C: Cortex of gray matterW: White matter

#77 Purkinje neurons #76b Pyramidal neurons

#74 Sympathetic ganglion cells

#75 Parasympathetic ganglion cells ( in Seminal vesicle)

Sensory and Autonomic Neurons (Parasympathetic – e.g. from vaginal wall) (DRG)