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The “Road Map”

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The “Road Map” PRACTICAL ROADMAP NERVOUS TISSUE DR N GRAVETT NEURONS • MOTOR • SENSORY Anterior (ventral) horn Dorsal root of spinal of spinal cord cord Multipolar Pseudounipolar ANTERIOR HORN CELLS • Slide 64 Spinal Cord (vervet monkey) Stain: Kluver and Berrera Technique NOTE: with this technique, myelin stains dark blue and basophilic substances such as rER and nuclei stain violet. In this case we use “blue” and “purple” to describe the staining and not eosinophilic and basophilic. SPINAL CORD Anterior Ventral Horn Arachnoid Ventricle Pia Mater Grey Matter White Matter Posterior Horn Dura Mater Dorsal ANTERIOR HORN CELL Neuropil Cell Body Dendrite Vesicular Nucleus Nucleolus Nucleus of Nissl Bodies Neuroglial Cell ANTERIOR HORN CELL Neuropil Cell Body Vesicular Nucleus Nucleolus Nissl Body Nucleus of Neuroglial Cell Dendrite Nissl Body Axon Hillock Axon SPINAL (DORSAL ROOT) GANGLION CELLS • Slide 62 Spinal Ganglion Stain: H&E NOTE: The spinal ganglion is also known as the dorsal root ganglia and contains pseudounipolar neuron cell bodies. SPINAL (DORSAL ROOT) GANGLIA Cell Bodies Processes (Axons and Dendrites) SPINAL (DORSAL ROOT) GANGLIA Cell Bodies Processes (Axons and Dendrites) NOTE: The neuronal cell bodies of the dorsal root ganglia are “clumped” together, and one cannot see any processes entering or leaving the cell bodies. The processes (axons and dendrites) are seen towards the edge/periphery of the group of cell bodies. SPINAL (DORSAL ROOT) GANGLIA Satellite cells (arranged in ring like fashion around the cell body) Cell Body Nucleolus Vesicular Fine Granular Nucleus Nissl Substance Nucleus of Satellite cell PERIPHERAL BRANCH OF A SPINAL NERVE • Slide 32 Median Nerve Stain: Mallory’s Technique NOTE: Three dyes are used in Mallory’s technique, which results in collagen fibres (such as connective tissue) staining blue, the “neurokeratin” staining red, and nuclei staining reddish-orange PERIPHERAL NERVE Myelinated Axons Vein L.S. L.S. Adipose L.S. Tissue Skeletal Vein Muscle Artery T.S. T.S. Perineurium Artery Epineurium PERIPHERAL NERVE Connective Tissue Coverings Myelinated Axons Endoneurium Perineurium Epineurium PERIPHERAL NERVE (L.S. HP) Endoneurium Central Axon (Unstained) Node of Ranvier Schwann Cell Nucleus Myelin Sheath (Neurokeratin) PERIPHERAL NERVE (T.S. HP) Central Axon Schwann Cell (Unstained) Nucleus Myelin Sheath (Neurokeratin) Schwann Cell Nucleus Endoneurium Endoneurium Perineurium Blood Vessel (BV) BV Epineurium PERIPHERAL BRANCH OF A SPINAL NERVE • Slide 26 Neuro-vascular Bundle (Axillary Sheath) Stain: H&E NOTE: This is a demonstration slide. All the same features as mentioned previously for the peripheral nerve will be identifiable, only the staining reaction will be different. PERIPHERAL NERVE Neuro-vascular Bundle Nervous Tissue Vein Artery Lymphiod Tissue Nervous Tissue Adipose Tissue Nervous Tissue PERIPHERAL NERVE Neuro-vascular Bundle Perineurium Epineurium Axons Adipose Tissue PERIPHERAL NERVE Neuro-vascular Bundle Fibroblast Nucleus Endoneurium Blood Vessel Axon Myelin Sheath Schwann Cell Nucleus Perineurium NEUROMUSCULAR JUNCTION • Slide 4 Striated Skeletal Muscle (Snake) Stain: H&E and Gold Impregnation NOTE: This is a demonstration slide. This is whole mount of striated skeletal muscle of the snake impregnated with gold to demonstrate the nerve fibres. NEUROMUSCULAR JUNCTION Nerve Fibres Striated Skeletal Muscle NEUROMUSCULAR JUNCTION Striated Skeletal Muscle Nerve Fibres Axon Axon Terminal / Motor End Plate AUTONOMIC NERVE AND GANGLIA • Slide 54 Wall of Vagina Stain: H&E NOTE: This is a demonstration slide. AUTONOMIC NERVE AND GANGLIA Processes (Axons/Dendrites) Satellite Nerve Cell Body Cell containing fine Nucleus granular Nissl Substance .
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