Medical School Histology Basics Muscle VIBS 243 lab

Medical School Histology Basics Muscle VIBS 243 lab Larry Johnson Texas A&M University

MUSCLE Function and Features Function: • Generation of contractile force • Locomotion of multicellular animals, beating of their hearts, and movement of their internal organs depends on muscles of different types. Distinguishing features: • High concentration of contractile proteins actin and myosin arranged either diffusely in the cytoplasm (smooth muscle) or in regular repeating units called sarcomeres (striated muscles, e. g. , cardiac and skeletal muscles) • All three muscle types comes from mesoderm

TYPES OF MUSCLE • Ref code #8 SKELETAL MUSCLE – VOLUNTARY, LARGE AND MULTINUCLEATED CELLS, STRIATED • CARDIAC MUSCLE – INVOLUNTARY, MONONUCLEATED AND BRANCHED CELLS, STRIATED • SMOOTH MUSCLE – INVOLUNTARY, MONONUCLEATED, NON-STRIATED

Ref code #5

Ref code # 5, 8 Smooth muscle no striations

Ureter (Slide 262 smooth muscle) Ref code # 5, 8 Connective tissue Transitional epithelium Connective tissue Smooth muscle fibers are long, spindle-shaped cells shown here as bundles of cells

Slide 19678 Smooth muscle and psudostratified columnar epithelium in ductus deferens (toluidine blue) Smooth muscle cells Ref code #8

Slide 32409: Rat intestine (toluidine blue) Central lacteal epithelium Gut lumen Muscularis externa smooth muscle,

Slide 32409: Rat intestine (toluidine blue) vein epithelium lacteal Auerbach’s plexus Meissner’s plexus Smooth muscle, Muscularis externa, Muscularis mucosa,

Duodenum (Slide 152) Smooth muscle longitudinal profiles Transverse profiles of smooth muscle cells sarcoplasm in these cells have no regular cross striations longitudinal and transverse profiles of smooth muscle cells

243 PAS staining of smooth muscle cell basement membrane in the stomach Smooth muscle cell nuclei

Smooth muscle; EM 9 of smooth muscle cells, note organelles 1. Nucleus of smooth muscle cell 2. Secondary lysosome 3. Mitochondrion

10 f EM 10 f: Arteriolar wall; 30, 000 x 1. Apical caveolae 2. Collagen 3. Dense bodies 4. Elastic fiber 5. Endothelial cell 6. Nuclear pore 7. RER

Smooth muscle; EM 10 e of smooth muscle cell. Note nerve attachment 1. Smooth muscle cell 2. Collagen 3. Nerve ending 4. Mitochondrion

Ref code # 5, 6, 8 Individual cells

Slide 136: Tongue, monkey Connective tissue of the perimysium capillaries nerve Skeletal muscle cells Perimysium

Slide HISTO 007: Skeletal muscle – nerve and Ref code #5 motor end plates Motor end plates in skeletal muscle One nerve innervates several muscle cells Histo 07 Skeletal muscle cells Slide HISTO 007: Skeletal muscle motor end plates

Slide 136 SKELETAL MUSCLE Slide 136: Tongue, monkey Anisotropic to polarized light =“A” band = dark band Isotropic to polarized light = “I” band = light band A band I band Ref code #6

Ref code # 5, 6, 12 Eliana

Slide 136: Tongue, monkey Skeletal muscle nuclei Fasciculi Endomysium Muscle cells skeletal muscle nuclei, Connective tissue of perimysium striations

Slide 136: Tongue, monkey Capillaries in skeletal muscle endomysium

211 -001 Skeletal muscle Striations = A&I bands skeletal muscle cell nuclei,

Cross striations in skeletal muscle cells (Slide 211 -001) 211 Skeletal muscle cells A band Z disc I band

EM 10; skeletal muscle; 30, 000 x 1. Mitochondria 2. Sarcoplasmic reticulum 3. Terminal cisternae

137 Esophagus – skeletal and smooth muscle Connective tissue nerve

Ref code #6 Contracted skeletal muscle cells have small I bands EM 10 a: Endothelial cells lining capillary with pericyte in the vessel wall; 20, 000 x 1. Lumen 2. Endothelial cell 3. Tight junction

Nerve – muscle interface at the motor end plates Muscle spindles stretch receptors Muscle fibers inside a connective tissue capsule Ref code #5

Slide HISTO 007 skeletal muscle cells Nerve – muscle interface at the motor end plates Note the motor end plates in several skeletal muscle cells

Muscle spindle #19753 Muscle spindles Intrafusal fibers inside the capsule Ref code #5

136 Tongue Muscle spindles capillaries Intrafusal fibers inside the capsule Muscle cells nerve fibroblasts Muscle cells

Skeletal muscle cells 211 Cardiac muscle cells Intercalated disc = cell attachments 225 Ref code #5

EM 10 b Ref code # 18

225 Intercalated disc in cardiac cells of the Heart, epicardium A band I band

Ref code #5

Slide 226 Cardiac muscle cells are striated Cardiac muscle cells are branched Cardiac cells are separated at the intercalated discs revealing the shape of individual cells, that the cells are branched, and the nuclei are in the center of cells. Ref code #6

Slide 226 Cardiac muscle cells are striated Cardiac muscle cells Cardiac cells can accumulate a high density of lipofuscin granules resulting from incomplete lysosomal digestion within the cell

Heart Internodal connections Ref code # 16

Histo 0 23 heart muscle Cardiac muscle cells Purkinje fibers Ref code # 16

Ref code #6 Intercalated discs EM 10 b cardiac muscle cells

EM 10 b Gap junctions Intercalated discs Ref code #8

CARDIAC MUSCLE – Skeletal muscle – triad located at A-I junction Diad located at Z disc Diad = (T tubule + one end of SER) TRIAD = (T TUBULE + TWO ENDS OF SER) Ref code # 6, 12

EM 10 b Skeletal muscle cell triad Cardiac muscle cell diad

Many illustrations in these VIBS Histology You. Tube videos were modified from the following books and sources: Many thanks to original sources! 1. Alberts, et al. , 1989. Molecular Biology of the Cell. 2 nd Edition. Garland Publishing, Inc. New York. ISBN 0 -8240 -3695 -6. 2. Alberts, et al. , 1994. Molecular Biology of the Cell. 3 nd Edition. Garland Publishing, Inc. New York. ISBN 0 -8153 -1619 -4. 3. Bloom, W. and Fawcett, D. W. , 1968. A Textbook of Histology. 9 th Edition. W. B. Saunders Company. Philadelphia. Library of Congress #67 -17445. 4. Elias, H. et al. , 1978. Histology and Human Microanatomy. A Wiley Medical Publication. John Wiley & Sons, New York. ISBN 0 -47104929 -8. 5. Eroschenko, V. 2000. Di Fiore’s Atlas of Histology with Functional Correlations. 9 th Edition. Lippincott Williams & Wilkins. Philadelphia. ISBN 07817 -2676 -X. 6. Fawcett, D. W. , 1986. Bloom and Fawcett. A Textbook of Histology. 11 th Edition. W. B. Saunders Company. Philadelphia. ISBN 0 -72161729 -8. 7. Fawcett, D. W. , 1986. Bloom and Fawcett. A Textbook of Histology. 12 th Edition. Chapman and Hall. New York. ISBN 0 -412 -04691 -1. 8. Guyton, A. C. 1971. Textbook of Medical Physiology. 4 th Edition. W. B. Saunders Company. Philadelphia. Library of Congress # 74118589. 9. Ham, A. W. 1974. Histology. 7 th Edition. J. B. Lippincott Company. Philadelphia. ISBN 0 -397 -52062 -X. 10. Ham, A. W. and Cormack, D. H. 1979. Histology. 8 th Edition. J. B. Lippincott Co. Philadelphia. ISBN 0 -397 -52089 -1. 11. Junqueria, et al. , 1995. Basic Histology. 8 th Edition. Appleton and Lange. Norwalk, Connecticut. ISBN 08385 -0567 -8. 12. Junqueira, et al. , 1998. Basic Histology. 9 th Edition. Appleton and Lange. Stamford, Connecticut. ISBN 0 -8385 -0590 -2. 13. Knobil, E. et al. 1988. The Physiology of Reproduction. Volume 1. Raven Press. New York. ISBN 0 -88167 -281 -5. 14. Langley, et al. , 1974. Dynamic Anatomy and Physiology. 4 th Edition. Mc. Graw-Hill Book Company. New York. ISBN 0 -07 -036274 -2. 15. Mescher, A. L. , 2010. Junqueira’s Basic Histology Text and Atlas. 12 th Edition. Mc. Graw Hill Medical. New York. ISBN 978 -0 -07 -1604314. 16. Tuttle, W. W. and Schottelius, B. A. 1969. Textbook of Physiology. 16 th Edition. The C. V. Mosby Company. Saint Louis. Library of Congress # 7589848. 17. Varner, D. et al. 1991. Diseases and Management of Breeding Stallions. American Veterinary Publications. Goleta, California. ISBN 0939674 -33 -5. 18. Von Hagens, Gunther and A. Whalley, 2007. Body Worlds – The Anatomical Exhibition of Real Human Bodies. ISBN 978 -3 -937256 -04 -7 19. Weiss, L. 1983. Histology: Cell and Tissue Biology. 5 th Edition. Elsevier Biomedical. New York. ISBN 0 -444 -00716 -4. 20. Weiss, L. and Greep, R. 1977. Histology. 4 th Edition. Mc. Graw-Hill Book Company. New York. ISBN 0 -07 -069091 -X.

Test Questions on Muscle Which is (are) true about striated muscle? a. The “A” band = dark band = anisotropic to polarized light b. The “I” band = light band = isotropic to polarized light c. The endomysium is delicate connective tissue around individual myofibrils d. a & b e. a, b, & c Which types of muscle have nuclei in the center of its cells and are involuntary: a. Smooth muscle b. Cardiac muscle c. Skeletal muscle d. a and b e. a, b and c Which is/are related to stimulation of muscle contraction: a. Motor end plate b. Gap junctions c. Purkinje fibers d. a and b e. a, b and c

In summary

Big Bend National Park, TX

The end of