CONNECTIVE TISSUE

Maj Rishi PokhrelAnatomy

NAIHSwww.slideshare.net

At the end of this class you should be able to…

• Describe characteristics & components of CT• Classify CT• Correlate CT type with their function

DEFINITION

“Connective tissues (CT) are a group of

tissues which connects or binds other

tissues in the body”

CHARACTERISTICS

• Predominantly intercellular material (matrix)• Cells widely spaced• Development – mesoderm, neural crest

(head region)• Blood vessels – few supply• Classification – based on matrix, cells, fibres

Components

Cells Matrix

Ground substance FIBERS

COMPOSITION: CONNECTIVE TISSUE

Composition

Components

Cells

Fixed

Fibroblasts

Adipocytes

Persistent mesenchymal

cells

Wandering

Macrophage

Mast cells

Plasma cells

Pigment cells

Eosinophil

Neutrophil

Matrix

Ground substance

Proteoglycans GAG /MPS

SO4

Non SO4

Fibers

Collagen

Elastic

Reticular

CONNECTIVE TISSUE

CELLS OF CONNECTIVE TISSUE

Cell Fibroblast Adipocyte Macrophage

Features Secrete matrix, numerous Lipocytes / fat cells Histiocytes, nomadic

Shape Spindle / fusiform with irregular surface

Oval, round or polygonal Irregular with filopodia

Size Avg 50 um 15-20 um

Nucleus Large, central , open faced At one side Small indented, kidney shaped

Cytoplasm Markedly basophilic (rER) Peripheral ring of cytoplasm, fat globules, signet ring appearance

Cytogranuales & vacuoles, stains deeply

Function Secrete EC matrix Formation & storage of fat

Phagocytic

Site Abundant during healing in all CT Many together forms giant cells

Special stain Frozen section, Sudan III-> red, Osmic acid -> black, Sudan black -> black

Cell Mast cell Plasma cell Pigment cell

Features Formed by B lymphocytes Chromatophores

Shape Round or oval Round or oval irregular

Size 12 um Upto 15 um

Nucleus Central, small Spherical & eccentric; cartwheel appearance, clock face

Cytoplasm Cyto-granuales, basophilic

Basophilic, rich in rER

Function Secrete histamine, heparin

Store Ab in cyto-granuales; russel’s bodies

Contain pigment - melanin

Site Inflammation, allergy, hypersensitivity

skin

Special stain For granules: toluidine blue, Methylene blue, alcian blue

FIBRES

• COLLAGEN

• ELASTIC

• RETICULAR

Collagen

Types of collagen

• I – fibrous supporting tissue, dermis, tendon, ligament, bone

• II – Hyaline cartilage, fine fibrils• III – reticular• IV- Mesh like, basement membrane• VII – anchoring fibrils of BM

Collagen

Ligament -TS

Ligament - LS

Elastic fibers

Reticular fibers

Collagen Elastic ReticularColor Pearly white Yellow -No Largest Next > In emb CTStain & appearance

Dull pink with eosin Bright, highly refractive

Not stained by H & E

Protein Collagen Elastin Reticulinthickness 1-12 um 0.1-0.2 um thinnestFeatures Wavy, do not branch, run

in bundles< wavy, branch, run singly

Straight, branch & anastomose-reticulum

Special stain Van gieso: red; AgNO3: brown; Masson’s trichome: blue

Orcein: Black AgNO3: Black

Sites To provide strength; tendon, ligament etc.

To provide elasticity; lig nuche, vocal cords, lungs, aorta

To provide support; spleen, liver, lymph nodes, kidney, BM

GROUND SUBS

• Amorphous, transparent, semi-fluid gel

• Proteoglycans, hyaluronic acid (GAG), water

• Proteoglycans: chondroitin SO4, chondroitin

6 SO4, dermatan SO4, heparan SO4, heparin

SO4, keratan SO4

Uronic acid

Amino sugar

Uronic acid

Amino sugar

Uronic acid

Amino sugar

Uronic acid

Amino sugar

N-acetyl glucosamineor

N-acetyl galactosamine

Hyaluronic acid• Predominant• No SO4 side chain• Not linked with protein

GAG / MPS

N-acetyl glucosamineor

N-acetyl galactosamine Other GAGs• SO4 side chain• linked with protein• Proteoglycans

Protein

SO4

Uronic acid

Amino sugar

Uronic acid

Amino sugar

Uronic acid

Amino sugar

Uronic acid

Amino sugar

Assignment

• Classification of CT

CLASSFICATION OF C. T.• Types of cells• Types of fibres• Amount of ground subs• Location

Connective tissue

Adult

Ordinary

Loose

Areolar

Adipose

Reticular

Dense

Regular

Tendon

Ligament

Aponeurosis

Irregular

Subcutaneous tissue

Specialized

Blood

Cartilage

Bone

Fetal

AREOLAR TISSUE

AREOLAR TISSUE

ADIPOSE TISSUE

ADIPOSE TISSUE

ADIPOSE TsSUDAN IV

TENDON L.S.

TENDON L.S.

TENDON L. S.

TENDON T.S.

TENDON T. S.

LIG NUCHAE L.S.

LIG NUCHAE L.S.

LIG NUCHAE T.S.

LIG NUCHAE T.S.

FETAL C T

FETAL C T

DENSE IRREGULAR C T & ADIPOSE Ts

Assignment

• Basement membrane

?