Nervous And Muscle Tissue Lab

Front 1

Back 1

Figure 5-1 (cerebrum)
Cerebrum, fast blue stained. The distribution of superficial grey matter (cerebral cortex) and deeper white matter is demonstrated by fast blue staining which is specific for myelinated axons.

Front 2

Back 2

Figure 5-1 (cerebrum)
Pyramidal neurons, which can be found in the cortical grey matter, are large and roughly pyramid-shaped. They possess a prominent, dark staining nucleolus that is visible inside a pale nucleus

Front 3

Back 3

Figure 5-1 (cerebrum)
Lipofuscin (age pigment) is often visible as a darker, magenta colored inclusion within the cytoplasm of the soma.

Front 4

Back 4

Figure 5-2 (cerebellum)
Cerebellum, H&E stained. Grey and white matter distribution is similar to the cerebrum. However, cerebellar cortex consists of three distinct layers of gray matter which are readily visualized using H&E stain.

Front 5

Back 5

Figure 5-2 (cerebellum)
The innermost granular layer (G) contains a high density of small granular cell neurons. The somas of large Purkinje neurons are located in the Purkinje cell layer (P), while the extensive dendritic arborizations of Purkinje cells occupy most of the molecular layer (M). Dark staining nuclei of other neurons are also scattered throughout the molecular layer.

Front 6

Back 6

Figure 5-2 (cerebellum)
The innermost granular layer (G) contains a high density of small granular cell neurons. The somas of large Purkinje neurons are located in the Purkinje cell layer (P), while the extensive dendritic arborizations of Purkinje cells occupy most of the molecular layer (M). Dark staining nuclei of other neurons are also scattered throughout the molecular layer.

Front 7

Back 7

Figure 5-3 (Purkinje cell structure)
Routine staining protocols readily identify the large somas and proximal dendrites of Purkinje cells (top), but do not detect most of the structural complexity of the dendritic branches

Front 8

Back 8

Figure 5-3 (Purkinje cell structure)
Figure 5-3 (Purkinje cell structure)
Complete structural detail of neurons requires use of more selective staining protocols, such as the Golgi (silver) staining method (bottom), or fluorescent imaging (not shown).

Front 9

Back 9

Figure 5-4 (spinal cord)
Cross section through spinal cord, cervical region. Fast blue stained.

Front 10

Back 10

Figure 5-5 (motor neurons)
Cervical spinal cord, fast blue stained. Large multipolar motor neurons are easily visible throughout the ventral horn. Cell bodies and one or more dendrites are typically observed for most motor neurons. Aging pigment is also frequently present. The dense tissue surrounding neuronal cell bodies is a complex tangle of dendrites, axons, and glia, often referred to as neuropil.

Front 11

Back 11

Figure 5-5 (motor neurons)
Cervical spinal cord, fast blue stained. Large multipolar motor neurons are easily visible throughout the ventral horn. Cell bodies and one or more dendrites are typically observed for most motor neurons. Aging pigment is also frequently present. The dense tissue surrounding neuronal cell bodies is a complex tangle of dendrites, axons, and glia, often referred to as neuropil.

Front 12

Back 12

Figure 5-5 (motor neurons)
Cervical spinal cord, fast blue stained. Large multipolar motor neurons are easily visible throughout the ventral horn. Cell bodies and one or more dendrites are typically observed for most motor neurons. Aging pigment is also frequently present. The dense tissue surrounding neuronal cell bodies is a complex tangle of dendrites, axons, and glia, often referred to as neuropil.

Front 13

Back 13

Figure 5-6 (motor neuron structure)
Motor neuron from spinal ventral horn, Nissl stained. This detailed image reveals Nissl bodies within the soma and proximal portions of several dendrites. Background staining reveals the structure of the axon and axon hillock, which are devoid of Nissl bodies. The cell nucleus is pale (also lacking Nissl bodies) and contains a dense nucleolus.

Front 14

Back 14

Figure 5-7 (peripheral nerve)
Cross section of peripheral nerve, stained with H&E (above) and OsO4 (below). Most fascicles contain both myelinated and non-myelinated axons. Observe the three layers of connective tissue that surround the whole nerve (epineurium), fascicles (perineurium), or individual axons (endoneurium). In some preparations, whorls of neurokeratin present in myelin sheaths are visible as an artifact.

Front 15

Back 15

Figure 5-7 (peripheral nerve)
Cross section of peripheral nerve, stained with H&E (above) and OsO4 (below). Most fascicles contain both myelinated and non-myelinated axons. Observe the three layers of connective tissue that surround the whole nerve (epineurium), fascicles (perineurium), or individual axons (endoneurium). In some preparations, whorls of neurokeratin present in myelin sheaths are visible as an artifact.

Front 16

Back 16

Figure 5-7 (peripheral nerve)
Cross section of peripheral nerve, stained with H&E (above) and OsO4 (below). Most fascicles contain both myelinated and non-myelinated axons. Observe the three layers of connective tissue that surround the whole nerve (epineurium), fascicles (perineurium), or individual axons (endoneurium). In some preparations, whorls of neurokeratin present in myelin sheaths are visible as an artifact.

Front 17

Back 17

Figure 5-8 (teased peripheral axons)
Longitudinal sections of axons teased from a peripheral nerve and stained with OsO4. Distinguish nodes of Ranvier from clefts of Schmidt-Lanterman. The latter are found only in peripheral white matter.

Front 18

Back 18

Figure 5-9 (dorsal root ganglion)
Dorsal root (spinal) ganglion, H&E stained. The large cell bodies of pseudounipolar sensory neurons possess centrally located nuclei and are surrounded by numerous glial satellite cells. Spoke-like neuro-keratin structures surround sensory cell bodies as artifacts of slide preparation. Observe the thick connective tissue capsule which surrounds the ganglion as well as the numerous nerve fibers passing through the ganglion interior.

Front 19

Back 19

Figure 5-9 (dorsal root ganglion)
Dorsal root (spinal) ganglion, H&E stained. The large cell bodies of pseudounipolar sensory neurons possess centrally located nuclei and are surrounded by numerous glial satellite cells. Spoke-like neuro-keratin structures surround sensory cell bodies as artifacts of slide preparation. Observe the thick connective tissue capsule which surrounds the ganglion as well as the numerous nerve fibers passing through the ganglion interior.

Front 20

Back 20

Figure 5-9 (dorsal root ganglion)
Dorsal root (spinal) ganglion, H&E stained. The large cell bodies of pseudounipolar sensory neurons possess centrally located nuclei and are surrounded by numerous glial satellite cells. Spoke-like neuro-keratin structures surround sensory cell bodies as artifacts of slide preparation. Observe the thick connective tissue capsule which surrounds the ganglion as well as the numerous nerve fibers passing through the ganglion interior.

Front 21

Back 21

Figure 5-10 (sympathetic ganglion)
Sympathetic ganglion, H&E stained. Numerous cell bodies of sympathetic post-ganglionic neurons are visible throughout the ganglion. Note the eccentrically positioned nuclei, in contrast to the central nuclei of spinal ganglionic neurons. Satellite cells surround the cell bodies, but are fewer in number than in spinal ganglia. In addition to glial cells, the space around the multipolar neurons is densely packed with dendritic processes.

Front 22

Back 22

Figure 5-10 (sympathetic ganglion)
Sympathetic ganglion, H&E stained. Numerous cell bodies of sympathetic post-ganglionic neurons are visible throughout the ganglion. Note the eccentrically positioned nuclei, in contrast to the central nuclei of spinal ganglionic neurons. Satellite cells surround the cell bodies, but are fewer in number than in spinal ganglia. In addition to glial cells, the space around the multipolar neurons is densely packed with dendritic processes.

Front 23

Back 23

Figure 5-10 (sympathetic ganglion)
Sympathetic ganglion, H&E stained. Numerous cell bodies of sympathetic post-ganglionic neurons are visible throughout the ganglion. Note the eccentrically positioned nuclei, in contrast to the central nuclei of spinal ganglionic neurons. Satellite cells surround the cell bodies, but are fewer in number than in spinal ganglia. In addition to glial cells, the space around the multipolar neurons is densely packed with dendritic processes.

Front 24

Back 24

Figure 5-11 (parasympathetic ganglion)
Parasympathetic ganglion from Aurbach’s plexus in jejunum, H&E stained. Cell bodies of multipolar post-ganglionic neurons are visible as well as multiple glial satellite cells. These parasympathetic ganglia are small and lack a surrounding capsule. They can be found between the two layers of the muscularis externa within the wall of the GI tract.

Front 25

Back 25

Figure 5-11 (parasympathetic ganglion)
Parasympathetic ganglion from Aurbach’s plexus in jejunum, H&E stained. Cell bodies of multipolar post-ganglionic neurons are visible as well as multiple glial satellite cells. These parasympathetic ganglia are small and lack a surrounding capsule. They can be found between the two layers of the muscularis externa within the wall of the GI tract.

Front 26

Back 26

Figure 5-11 (parasympathetic ganglion)
Parasympathetic ganglion from Aurbach’s plexus in jejunum, H&E stained. Cell bodies of multipolar post-ganglionic neurons are visible as well as multiple glial satellite cells. These parasympathetic ganglia are small and lack a surrounding capsule. They can be found between the two layers of the muscularis externa within the wall of the GI tract.

Front 27

Back 27

Figure 5-12 (smooth muscle)
Jejunum, H&E stained. The muscularis externa is composed of two sheets of smooth muscle, which are perpendicular to one another. Myocytes of the inner, or circular layer, are oriented perpendicular to the long axis of the gut, whereas cells of the outer, or longitudinal layer, are oriented parallel to this axis. Individual smooth myocytes are difficult to distinguish; however, the single centrally located nuclei are clearly visible

Front 28

Back 28

Figure 5-12 (smooth muscle)
Jejunum, H&E stained. The muscularis externa is composed of two sheets of smooth muscle, which are perpendicular to one another. Myocytes of the inner, or circular layer, are oriented perpendicular to the long axis of the gut, whereas cells of the outer, or longitudinal layer, are oriented parallel to this axis. Individual smooth myocytes are difficult to distinguish; however, the single centrally located nuclei are clearly visible

Front 29

Back 29

Figure 5-12 (smooth muscle)
Jejunum, H&E stained. The muscularis externa is composed of two sheets of smooth muscle, which are perpendicular to one another. Myocytes of the inner, or circular layer, are oriented perpendicular to the long axis of the gut, whereas cells of the outer, or longitudinal layer, are oriented parallel to this axis. Individual smooth myocytes are difficult to distinguish; however, the single centrally located nuclei are clearly visible

Front 30

Back 30

Figure 5-13a (skeletal muscle l.s.)
Skeletal muscle, longitudinal section, H&E stained. Skeletal myofibers are very large, elongated, multinucleated cells. Many nuclei lie along the periphery of the cells. Skeletal myofibers have a very regular arrangement, and many fiber-shaped cells can be seen side-by-side. At higher magnifications, their striated appearance can be resolved as an alternating pattern of A-bands and I-bands (dark and light bands, respectively).

Front 31

Back 31

Figure 5-13a (skeletal muscle l.s.)
Skeletal muscle, longitudinal section, H&E stained. Skeletal myofibers are very large, elongated, multinucleated cells. Many nuclei lie along the periphery of the cells. Skeletal myofibers have a very regular arrangement, and many fiber-shaped cells can be seen side-by-side. At higher magnifications, their striated appearance can be resolved as an alternating pattern of A-bands and I-bands (dark and light bands, respectively).

Front 32

Back 32

Figure 5-13a (skeletal muscle l.s.)
Skeletal muscle, longitudinal section, H&E stained. Skeletal myofibers are very large, elongated, multinucleated cells. Many nuclei lie along the periphery of the cells. Skeletal myofibers have a very regular arrangement, and many fiber-shaped cells can be seen side-by-side. At higher magnifications, their striated appearance can be resolved as an alternating pattern of A-bands and I-bands (dark and light bands, respectively).

Front 33

Back 33

Figure 5-13b (skeletal muscle c.s.)
Skeletal muscle, cross section, H&E stained. Fascicles of muscle tissue (outlined in black above) are encased by sheaths of dense irregular connective tissue called perimysium. At higher magnifications connective tissue surrounding individual myofibers, or endomysium, can be observed. Multiple nuclei are frequently visible in the periphery of each myofiber.

Front 34

Back 34

Figure 5-13b (skeletal muscle c.s.)
Skeletal muscle, cross section, H&E stained. Fascicles of muscle tissue (outlined in black above) are encased by sheaths of dense irregular connective tissue called perimysium. At higher magnifications connective tissue surrounding individual myofibers, or endomysium, can be observed. Multiple nuclei are frequently visible in the periphery of each myofiber.

Front 35

Back 35

Figure 5-13b (skeletal muscle c.s.)
Skeletal muscle, cross section, H&E stained. Fascicles of muscle tissue (outlined in black above) are encased by sheaths of dense irregular connective tissue called perimysium. At higher magnifications connective tissue surrounding individual myofibers, or endomysium, can be observed. Multiple nuclei are frequently visible in the periphery of each myofiber.

Front 36

Back 36

Figure 5-14 (cardiac muscle)
Cardiac muscle in longitudinal section (above) and cross section (lower right), H&E stained. Observe the less regular arrangement of the smaller, striated cardiomyocytes, as compared to skeletal myofibers. Many cells are branched as well as binucleate, with nuclei occupying a more central position compared with skeletal muscle cells. Intercalated discs can be observed at attachment sites between neighboring cardiac cells, when viewed in longitudinal section.

Front 37

Back 37

Figure 5-14 (cardiac muscle)
Cardiac muscle in longitudinal section (above) and cross section (lower right), H&E stained. Observe the less regular arrangement of the smaller, striated cardiomyocytes, as compared to skeletal myofibers. Many cells are branched as well as binucleate, with nuclei occupying a more central position compared with skeletal muscle cells. Intercalated discs can be observed at attachment sites between neighboring cardiac cells, when viewed in longitudinal section.

Front 38

Back 38

Figure 5-14 (cardiac muscle)
Cardiac muscle in longitudinal section (above) and cross section (lower right), H&E stained. Observe the less regular arrangement of the smaller, striated cardiomyocytes, as compared to skeletal myofibers. Many cells are branched as well as binucleate, with nuclei occupying a more central position compared with skeletal muscle cells. Intercalated discs can be observed at attachment sites between neighboring cardiac cells, when viewed in longitudinal section.

Front 39

Back 39

Figure 5-15 (neuromuscular junction)
Neuromuscular junctions between branching nerve terminals and skeletal muscle fibers.