Chapter 2Chapter 2 Chapter 2Chapter 2

Tissue repair

Department of pathology longjie

Repair ( 修复）

Would healing （创伤愈合）

Repair Repair (( 修复）修复） Repair Repair (( 修复）修复）

As cells and tissues are being injured,

events that contain the damage and

prepare the surviving cells to replicate are

set into motion.

Repair begins very early in the cell injury,

and involves two processes:

1. Regeneration ( 再生）

2. fibrosis （纤维性修复）

regeneration

再 生

Regeneration of injured tissue by

parenchymal cells of the same type .

types

Physiological regeneration

Pathological regeneration

Proliferative potential of different cell types

Labile cells

Stable cells

Permanent cells

不稳定细胞

稳定细胞

永久性细胞

Labile cellsLabile cells

Continuously dividing and dying Surface epithelia stratified squamous surfaces

cuboidal epithelia

columnar epithlium

transitional epithelium Hematopoietic cells

Stable cellsStable cells

Quiescent but can rapidly divide in response to injury

Parenchymal of solid glandular tissues: liver, kidney, pancreas

Endothelial cells lining blood vessels fibroblast Smooth muscle connective tissue

Permanent Permanent cellscells

Be terminally differentiated and nonproliferative in postnatal life

neurons Cardiac muscle cells

Regeneration of

different tissues

毛细血管的再生 angiogenesis

fibrosis

纤维性修复

Replacement by connective tissue,

resulting in a scar.

types

Granulation tissue ( 肉芽组织 )

Scar ( 瘢痕 )

Gross: pink , soft , granular

Micro:

proliferation of fibroblasts

new thin-walled, delicate capillaries

inflammatory cells

Granulation tissueGranulation tissue

脚的肉芽组织

肉芽组织

Granulation tissue

fibroblast

signaficationsignafication

risist infection and protect the wound surface ；

fill the deficiency and repair the injured tis

sue ；organize blood clotting, necrotic tissues o

r abnormal substances

Gross: tissue shrinkage, pale-gray ,

hard , lack of elasticity

Micro:

fibroblasts , new vessels avascular

inflammatory cells

collagen synthesis hyaline change

scarscar

effect

Good: 1.fill the defect, repair the tissue

2. More tensile strength than granulation tissue

bad: 1.scar shrinkage obstruction of tissue activity

2. Scaring conglutination ( 瘢痕性粘连）

3. Organ cirrosis （器官硬化）

4. Scar hyperplasia （瘢痕增生）

Wound Wound HealingHealing

A complex but orderly process, in

volving both parenchymal cells re

generation and the formation of c

onnective tissue scar.( 创伤愈合 )

Healing of skin Healing of skin woundwound

types

Healing by first intention (primary union)

一期愈合

Healing by second intention (sceondary union)

二期愈合

Healing of a clean , uninfected surgical incision approximated by surgical sutures.

1. Less fibrinclotted blood, granulation tissue and scar

2. Mild inflammation reaction

一期愈合模式图

large tissue defects, infected and irregular incision.

1. Much larger amounts of granulation tissue and scar

2. Extensive inflammation reaction

二期愈合模式图

Healing of skin wound

influences of influences of healinghealing

Age

nutrition

infection

Blood supply

radiation

glucocorticoids

Mechanical factors

Healing of bone Healing of bone

fracture fracture (self – study)(self – study)