1. Jeanne A Pawitan Basic tissues Epithelium Connective tissues Muscles Nervous tissue Jeanne Adiwinata Pawitan Dept. of Histology FMUI

2. Jeanne A Pawitan Basic tissues Epithelium: cells, intercellular substance/extracellular matrix – basement membrane *Connective tissue: intercellular substance↑ Muscle: muscle cells* = muscle fibers Nerve*: °Neurons °Neuroglial cells (support, protect neurons)

3. Jeanne A Pawitan Epithelium

4. Jeanne A Pawitan Epithelium (and glands) Layers °Single Simple (Pseudostratified) °Multiple Stratified (Transitional) Shape °Squamous °Cuboidal °Columnar (torax) Location

5. Jeanne A Pawitan Polarity and cell surface specializations Morphological domain Biochemical domain Polarity Functional domain  Apical domain – free surface – lumen  Basolateral domain  Basal - basal lamina  Lateral – other cells

6. Jeanne A Pawitan Apical domain - lumen Microvilli Cilia °Kinocilia °Stereocilia Ion channels Aquaporins Carrier proteins H + - ATPase Glycoproteins Hydrolytic enzymes

7. Jeanne A Pawitan Basolateral domain Intercellular interdigitation, basal enfoldings Junctional specialization Receptors °Hormones °Neurotransmitters Na + -K + ATPase Ion channels Sites for constitutive secretions

8. Jeanne A Pawitan Junctional specialization Lateral membrane specialization – terminal bars (LM) – junctional complexes (EM) °Occluding junction, tight junction, zonula occludens °Adhering junction Zonula adherens -zonulae adherentes Fascia adherens Macula adherens (desmosome) - hemidesmosome °Gap junction

9. Jeanne A Pawitan Connective tissue

10. Jeanne A Pawitan Connective tissues Mesenchyme (embryo) – mucosa /gelatinosa Connective tissue proper °Loose (areolar) connective tissue areolar CT °Reticular connective tissue °Adipose tissue °Dense connective tissue Dense regular connective tissue  Dense regular collagenous connective tissue  Dense regular elastic connective tissue Dense irregular connective tissue Specialized connective tissue (cartilage, bone, blood)

11. Jeanne A Pawitan Cells of connective tissue Mesenchymal cells - mesenchyme Fibroblasts/fibrocytes Histiocytes/macrophages Mast cells Pericytes Adipose cells Reticular cells – reticular CT Transient cells: plasma cells, leucocytes, macrophages

12. Jeanne A Pawitan Intercellular substance/ extracellular matrix Ground/amorphous substance (gel like)– tissue fluid °Glycosaminoglycans (GAG) (hyaluronic acid, heparin, sulfated GAG) °Proteoglycans ( certain GAG – Protein) °Adhesive glycoproteins (fibronectin, laminin, entactin, tenascin, chondronectin, osteonectin) Fibers °Collagen type I – VII Reticular (type III collagen) °Elastic fibers

13. Jeanne A Pawitan Basement membrane Basal lamina °Lamina lucida laminin, entactin Transmembrane protein: integrin, dystroglycan °Lamina densa (perlacan-type IV collagen meshwork-perlacan, fibronectin) Lamina reticularis: type I, III collagen

14. Jeanne A Pawitan Muscles

15. Jeanne A Pawitan Muscles Striated muscle – characteristic striation – specific arrangement of myofilament (contractile protein in a myofibril: myosin, actin)  parallel arrays regularly repeated arrangement  interdigitating in myofibril °skeletal muscle °cardiac muscle Smooth muscle  Myoepithelial cells –glandular unit in glands  Myofibroblast – wound contraction, tooth eruption

16. Jeanne A Pawitan Unique terms in muscle Sarcolemma = cell membrane Sarcoplasm = cytoplasm Sarcoplasmic reticulum = smooth surfaced endoplasmic reticulum (SER) Sarcosome = mitochondria muscle fiber = muscle cell

17. Jeanne A Pawitan Smooth muscle Location: wall of hollow organ - lumen °Digestive system °Reproductive system °Urinary system °Respiratory system °Ducts - large (glands) °Dermis (skin) Function: °contraction °Protein synthesis  extra cell: collagen, elastin, glycosaminoglycans, proteoglycans, growth factors

18. Jeanne A Pawitan Smooth muscle contraction - involuntary – controlled by °Autonomic nervous system (sympathetics, parasympathetics) °Hormone: bradykinin °Local physiological condition Every fiber – lined by external lamina (outside sarcolemma) °reticular fiber - embedded in external lamina – surrounding each muscle cell – function: control and unify the strength of muscle fiber contraction

19. Jeanne A Pawitan Smooth muscle fiber Shape : fusiform, elongated –Ø 5-6 μm, length - 0.2 mm Surrounded by sarcolemma (cell membrane) Nucleus - center – oval – 1-2 nucleolei – at contraction  nucleus  bottle opener HE: cytoplasm – homogenous – acidophilic Iron hematoxylin – in sarcoplasm: °Dense body – attached at the inside of cell membrane °Longitudinal lines  groups of myofilaments

20. Jeanne A Pawitan Smooth muscle fiber Form sheets/layers – usually 2 layers – perpendicular fibers –closely packed – thin part >< thick part °Cross section – fiber diameter ≠ – section - nucleus (+)/(-) Individual cell

21. Jeanne A Pawitan Innervation – smooth muscle fiber Neuromuscular junction usually en passant type °Bulging of axon °Containing synaptic vesicles Nor epinephrine – sympathetic Acetylcholine – parasympathetic Type °multi unit –individual innervation (iris, vas deferens °Intermediate (mixed 30-60% - individual) °Visceral – some fibers – 1 neuromuscular junction – gap junction/nexus (uterus, GI tract) – other influencing factor Humoral factor : oxytocin Micro environmental factor : stretching (intestines)

22. Jeanne A Pawitan Cardiac muscle Development: Myoepicardial mantle in splanchnic mesenchyme  epicardium + myocardium Cardiac muscle °Cardiac muscle fiber–branching-anastomosing  network – arranged in layers (laminae) °Between fibers – connective tissue °Connective tissue between laminae – contains: Blood vessels  capillaries  network –in connective tissue between each fiber Nerves conducting system – in heart

23. Jeanne A Pawitan Cardiac muscle fiber Striated, branching Length 15-80 μm Nucleus 1 (occasionally 2) – center – big –oval Between cells (at the end) - intercalated disk - consist of: °Transverse portion: facia adherens (  Z disk), desmosome °Lateral portion: gap junction (also found in regions - side by side contact – long.)

24. Jeanne A Pawitan Sarcoplasm contains Myofibrils Ø-1-2 μm –longitudinal –regularly arranged  striated (longitudinal section): °A band – (anisotropic on polarized light  dark) °I band– (isotropic on polarized  light) EM: Sarcoplasmic reticulum = SER °Network around myofibril °Function: intracellular Ca storage (< skeletal muscle) °Small terminals (terminal cisternae -) °The rest = longitudinal sarcotubule + branches °Contraction needs active transport of Ca from extra cell membrane contains junctional feet (= voltage gated Ca release channels)

25. Jeanne A Pawitan Sarcoplasm contains Organels °Mitochondria >>> - ½ volume – cardiac muscle °Myoglobin  O2 transport °Glycogen particle  energy source for contraction ( with lipid)

26. Jeanne A Pawitan Cardiac muscle fiber – T tubule EM: Sarcolemma – tubular invagination – transverse – branching - anastomosing  T tubule (transverse tubule) Intertwine among myofibril Location: around Z line – 1/sarcomere °Open to extra cellular compartment -lined by external lamina °Ø 2.5 X T tubule in skeletal muscle Function: facilitate conduction – depol. wave -along sarcolemma Associated with sarcoplasmic reticulum: T tubule + small terminals  dyad

27. Jeanne A Pawitan Myofibrils A band (dark) – H band (light) – M line I band (light) – Z line (Z disk, dark) Sarcomere = myofibril region between 2 Z line = 1 contractile unit Contraction: °I band - shortened °H band - disappeared °A band - constant °Z line - approaching each other

28. Jeanne A Pawitan Cardiac muscle fiber-atrium Ø < fiber in ventricle  myoendocrine cells Contains granules - cardiodilatin (CDD)/Atrial Natriuretic (Poly)peptide (ANP) – esp. in right atrium °ANP – regulation of fluid –electrolyte balance Efferent arteriole constriction  diuresis, sodium excretion↑ Sodium, water resorption in kidneys (renal tubules)↓  blood pressure ↓ - Vasodilatation inhibit the release of arginine-vasopressin (posterior hypophysis), and aldosterone (adrenal cortex)

29. Jeanne A Pawitan Skeletal muscle investments °Epimysium – muscle – irregular dense collagenous connective tissue °Perimysium – fascicles (bundles) - < dense °Endomysium – muscle fiber (cell) - reticular fiber, basal lamina / external lamina cell °Skeletal muscle fibers – striated – parallel °Satellite cells

30. Jeanne A Pawitan Skeletal muscle cells/fibers Development: myoblast – parallel  end –end  fused  myotube – formed myofibril  skeletal muscle fiber Shape: long, tubular – Ø 10-100μm Between fibers: endomysium + continuous capillaries – parallel to fiber Skeletal muscle fiber – non branching -striated - multinucleated Nuclei – periphery – in a row – inside cell membrane (sarcolemma) EM: Sarcolemma invaginate  T tubule (transverse tubule)

31. Jeanne A Pawitan Sarcoplasm: contains A lot of myofibril Ø-1-2 μm –longitudinal – along the fiber – regularly arranged  striation in longitudinal section: °A band – (anisotropic on polarized light  dark) °I band– (isotropic on polarized light  light) EM: Sarcoplasmic reticulum = smooth surface endoplasmic reticulum °Form a network around myofibril °Function: intracellular Ca storage (esc. terminal cysterna) °A-I junction – dilated  terminal cysterna The membrane has junctional feet (= voltage gated Ca release channels) °The rest = longitudinal sarcotubules + their branches

32. Jeanne A Pawitan T tubule Tubular invagination –transversal – branching- anastomosing – intertwine among myofibril Location: transversal plane - A-I junction  2 in each sarcomere To extra cell - open Associated with sarcoplasmic reticulum Function: facilitate conduction of depol wave along sarcolemma T tubule + 2 terminal cysternae  triad °function: spreading of depol wave – fast – from sarcolemma – trough out the cell – to terminal cysterna

33. Jeanne A Pawitan Myofibril A band (dark) – H band – pale –M line I band (light) –Z line, Z disk – thin, dark Sarcomere = myofibril area between 2 Z line = contractile unit of skeletal muscle fiber Contraction: °I band shortened °H band disappeared °A band remain unaltered °Z line – move closer together

34. Jeanne A Pawitan Satellite cells Satellite cells = regenerative cells Small cell – location: shallow depression – muscle cell’s surface External lamina – shared with muscle cell → inside external lamina Nucleus-one - > dense - > coarse

35. Jeanne A Pawitan Myotendinuous junction Connective tissue–muscle – tendon – continuous °Cells tapered – fluted (deeply folded) °Collagen fibers-tendon – penetrate Infoldings Endomysium – continuous – reticular fibers

36. Jeanne A Pawitan Innervation of skeletal muscle Motor nerve fibers (α motor neurons –axon- myelinated) branching – unmyelinated (Schwann cells +) – terminal dilated - myoneural junction (motor end plate) °Axon terminal °Synaptic cleft °Muscle cell membrane Sensory nerve fibers °muscle spindles – among muscle cells –stretch Rx °Golgi tendon organ (neurotendinuous spindle)– inhibitory feedback - α motor neurons - relax

37. Jeanne A Pawitan Regeneration - muscles Skeletal muscle – regeneration (+) °Skeletal muscle fiber ≠ mitosis °Satellite cells Injury: satellite cells - mitosis – hyperplasia At muscle building: satellite cell – muscle fiber - fusion  mass increase  hypertrophy Cardiac muscle - ≠ regeneration, fibroblast – connective tissue (scar) Smooth muscle – regeneration (+)

38. Jeanne A Pawitan Regeneration – smooth muscle Injury  formation of new fibers °Mitosis – smooth muscle fiber (GI tr., urin. tr.) °Differentiation - pericyte – blood vessel Uterus –pregnant – smooth muscle °hyperplasia - mitosis °hypertrophy

39. Jeanne A Pawitan Nervous tissue

40. Jeanne A Pawitan Neurons Cell body (soma, perikaryon) Dendrite (multiple) - branching Axon (single) – long - branching °Axon Hillock °Axon terminals, end bulbs, terminal boutons → synapse

41. Jeanne A Pawitan Specialized cells

42. Jeanne A Pawitan Specialized cells Protein secreting cells Steroid secreting cells Neuroendocrine cells Cells in organs → other modules

43. Jeanne A Pawitan Protein secreting cells Ex.: chief cells (stomach), acinar cells (pancreas) Shape: columnar, truncated pyramid, etc Basal cytoplasm - basophilic °Nucleus °Rich in RER, polysome Apical cytoplasm - acidophilic °Secretory granules – proenzyme (zymogen)

44. Jeanne A Pawitan Steroid secreting cells Ex: spongiocytes (adrenal cortex) Shape: polyhedral Cytoplasm °Extensive network of SER °Lipid droplets – appear vacuolated

45. Jeanne A Pawitan Neuroendocrine cells Argentaffin, argyrophilic – silver staining APUD= amine precursor uptake decarboxylation DNES= diffuse neuroendocrine system Location: epithelium/glands – systems Secretory granules –at basal cytoplasm/ near blood vessel

46. Jeanne A Pawitan Stem cells

47. Jeanne A Pawitan Stem cells Fertilization → 2-4 cells → morula (8 cells) →blastocyst °Trophectoderm → placenta °Inner cell mass → embryo ↓ Embryonic stem cells → determined stem cells (connective tissue, blood) → unipotential stem cells → differentiation (precursors of certain cells) → certain cells

48. Jeanne A Pawitan Stem cells Totipotent – can give rise to cells of all orders Pluripotent – can develop in any one of several possible ways, or affect more than one organ/tissue – multipotent Unipotent – can give rise to cells of one order only