8/10/2019 Epithelium I 2014 D2L

1/32

Epithelium I

Craig A. Canby, Ph.D.

Professor of Anatomy

8/10/2019 Epithelium I 2014 D2L

2/32

Set the Stage

Clinical teaser

Classification of epithelia

Specializations of the plasmalemma

Clinical teaser

2

8/10/2019 Epithelium I 2014 D2L

3/32

3

A mother brings her 10-year-old son to thepediatrician at a major University teaching medical

center. She is concerned about his chronicrespiratory problems and recurring episodes of earinfections. The physical examination revealsswollen nasal mucosa, impaired sense of smell,

and abnormal lung sounds. A nasal biopsy wasobtained and sent to pathology and imagingstudies were ordered.

Clinical teaser

8/10/2019 Epithelium I 2014 D2L

4/32

4

Epitheliumits everywhere

8/10/2019 Epithelium I 2014 D2L

5/32

Fig. 5.1 Ross Histology

Cell domains,

basal lamina,

and avascular

5

8/10/2019 Epithelium I 2014 D2L

6/32

The stria vascularis is aspecial type of epitheliumthat is vascular.

Located in the cochlearduct and producesendolymph.

Erythrocyte in capillary

Fig 25.16 Wheaters

Functional Histology, 5th

ed 6

8/10/2019 Epithelium I 2014 D2L

7/32

Characterstics used to classify epithelia

Number of cell layers

Cell shape in superficial layer

Presence of specializations of the plasma

membrane

7

8/10/2019 Epithelium I 2014 D2L

8/32

8

Types of epithelia

8/10/2019 Epithelium I 2014 D2L

9/32

WheatersFunctional Histology, 5thedition

Simple squamous

Fig. 5.1

9

Alveolus

Blood vessel

Mesothelium

FunctionsBlood-brain barrierFiltrationExchange

8/10/2019 Epithelium I 2014 D2L

10/32

Simple cuboidal

10

LocationsThyroid folliclesRenal tubulesDucts of glands

FunctionsAbsorptionSecretionBarrierConduit

8/10/2019 Epithelium I 2014 D2L

11/32

Simple columnar

11

Locations

StomachIntestines

Nonciliated

Ciliated

LocationUterine tubes

FunctionsAbsorptionSecretionBarrier

8/10/2019 Epithelium I 2014 D2L

12/32

Pseudostratified columnar, ciliated

12

Trachea

BronchiDucts of male reproductive system(stereocilia are present)

Functions

SecretionAbsorptionBarrierTransport

8/10/2019 Epithelium I 2014 D2L

13/32

Stratified squamous

13

Keratinized (K)

Nonkeratinzied

NonkeratinizedEsophagusDistal anal canalVagina

KeratinizedEpidermis

FunctionsBarrierProtection

8/10/2019 Epithelium I 2014 D2L

14/32

Fig 5.7 WheatersAtlas, 5thed

Squamous cell carcinoma

14

8/10/2019 Epithelium I 2014 D2L

15/32

Fig 5.8

Stratified cuboidalnot common

15

8/10/2019 Epithelium I 2014 D2L

16/32

Transitional (urothelium)

16

Locations

UretersUrinary bladderUrethra

Functions

BarrierProtectionDistension

8/10/2019 Epithelium I 2014 D2L

17/32

17

http://upload.wikimedia.org/wikipedia/commons/2/2c/Bladder_urothelial_carcinoma_%281%29_pT1.JPG

http://www.urologycenter.com/i/01_Bladder_Cancer.jpg

Transitional cell carcinoma

8/10/2019 Epithelium I 2014 D2L

18/32

Fig. 5-31. Color Textbook of Histology, 2nded

Plate 2, Ross Histology, 6thed

Plate 60, Ross Histology, 6thed

Metaplasia

18

8/10/2019 Epithelium I 2014 D2L

19/32

Specializations of the plasmalemma

Cilia:

motile

primary aka monocilium (nonmotile) nodal (motile)

Flagella

Microvilli

Stereocilia (stereovilli)

19

8/10/2019 Epithelium I 2014 D2L

20/32

20

Motile cilium

Fig 5-7. Ross Histology

9 + 2 array of MTs

Above array forms frombasal body (9 x 3)

DyneinATPase

8/10/2019 Epithelium I 2014 D2L

21/32

21

Ciliated respiratory epithelium

Fig 5.8. Histology A Text and Atlas, 6th

ed

8/10/2019 Epithelium I 2014 D2L

22/32

22

Primary aka monocilium (nonmotile) cilium

Fibroblast Epithelial cells of collecting tubule

Serve as chemosensors, osmoreceptors, and mechanoreceptorsMediate light, taste, and sound perceptionPivotal role in normal tissue morphogenesis

8/10/2019 Epithelium I 2014 D2L

23/32

23

Primary cilium and polycystic kidney disease

Note change ofspindle orientation

N Engl J Med 2011;364:1533-43

8/10/2019 Epithelium I 2014 D2L

24/32

Nodal cilia are locatedin the primitive node

NVP

8/10/2019 Epithelium I 2014 D2L

25/32

25Fig. 5.3. Histology A Text and Atlas, 6thed

Microvilli

8/10/2019 Epithelium I 2014 D2L

26/32

Fig. 3-17. Human Histology, 3rded

Cilium

and microvilli

26

Cross-sectional profilesof microvilli and cilium

8/10/2019 Epithelium I 2014 D2L

27/32

Fig. 3-15. WheatersFunctional Histology,4thed

Brush (striated) border and glycocalyx: PAS+

27

8/10/2019 Epithelium I 2014 D2L

28/32

Fig 5.4 Histology A Text and Atlas, 6th

ed

Stereocilia (stereovilli)male reproductive ducts

28

8/10/2019 Epithelium I 2014 D2L

29/32

Fig 5.5 Histology A Text and Atlas, 6

th

ed29

Stereocilia sensory epitheliumof inner ear

8/10/2019 Epithelium I 2014 D2L

30/32

30

A mother brings her 10-year-old son to thepediatrician at a major University teaching medical

center. She is concerned about his chronicrespiratory problems and recurring episodes of earinfections. The physical examination revealsswollen nasal mucosa, impaired sense of smell,

and abnormal lung sounds. A nasal biopsy wasobtained and sent to pathology and imagingstudies were ordered.

Clinical teaser

8/10/2019 Epithelium I 2014 D2L

31/32

31

Pathologic finding at the EM level

Referencenormal From patient

Figures 5.7 and F5.2.1

8/10/2019 Epithelium I 2014 D2L

32/32

Imaging studies

Fig 59-17 Sabiston Textbook ofSurgery, 18thed

Source of CT images unknown.

Findings Chronic sinusitis Bronchiectasis Situs inversus