Patho week2 ch 9

Acute Inflammation: Stage 1 Vascular Permeability

Summary

• Histamine and Bradykinin cause vasodilation and permeability of blood vessels, leading to fluid, WBCs, and platelets flooding to the site of injury.
• Capillary permeability allows WBCs in the fluid from capillaries to consume foreign material through phagocytosis.

Main Themes and Motifs

• Vasodilation and permeability of blood vessels
• Phagocytosis by WBCs

Acute Inflammation: Stage 2 Cellular Chemotaxis

Summary

• Microbial agents, endothelial cells, and WBCs attract platelets and other WBCs to the site of injury.
• Margination forms a protective wall, and cytokine/interleukin is released, leading to leukocytosis.

Main Themes and Motifs

• Chemotaxis of WBCs
• Leukocytosis

Cytokines and Interleukins

Summary

• Cytokines are proteins from glial cells in the nervous system that act as signaling molecules, stimulating the liver to release CRP and increasing or decreasing reactions.
• Interleukins are a subset of cytokines that moderate cellular behavior and act as messenger molecules between immune cells.

Main Themes and Motifs

• Signaling molecules
• Moderation of cellular behavior

Neutrophils and Monocytes

Summary

• Neutrophils are the first line of defense, with a lifespan of 10 hours to 2 days, and start phagocytosis.
• Monocytes are the largest WBCs that differentiate into macrophages and take over phagocytosis, indicating a more chronic process.

Main Themes and Motifs

• Phagocytosis
• Chronic inflammation

Acute Inflammation: Stage 3 Systemic Response

Summary

• Prostaglandins, leukotrienes, TNF alpha, interleukins, and pyrogens control the systemic response.
• Prostaglandins are responsible for pain, leukotrienes help produce mucus, TNF alpha comes from monocytes, interleukins play a role in cell growth, and pyrogens act on the hypothalamus and activate heat, leading to fevers.

Main Themes and Motifs

• Systemic response

Mind Map: Acute Inflammation

Central Idea

Acute inflammation is a process that occurs in response to injury or infection.

Main Branches

1. Stage 1 Vascular Permeability
2. Stage 2 Cellular Chemotaxis
3. Stage 3 Systemic Response
4. Tissue Healing

Stage 1 Vascular Permeability

• Histamine (Mast Cells) + Bradykinin = vasodilation and permeability of blood vessels
• Fluids, WBCs, and platelets flood to the site of injury
• Capillary permeability
• WBC in the fluid that comes from capillaries consumes foreign material = phagocytosis

Stage 2 Cellular Chemotaxis

• Microbial agents, endothelial cells, and WBCs attract platelets and other WBCs to the site of injury
• Margination protective wall is formed
• Cytokine/Interleukin gets released
• Leukocytosis occurs
• Neutrophils: first line defense, start phagocytosis
• Monocytes: largest WBC, differentiate into macrophages, take over phagocytosis, indicates the more chronic process

Stage 3 Systemic Response

• Controlled by prostaglandins, leukotrienes, TNF alpha, interleukins, pyrogens
• Prostaglandins: responsible for pain
• Leukotrienes: helps produce mucus
• TNF alpha: come from monocytes
• Interleukins: play a role in cell growth
• Pyrogens: act on hypothalamus and activate heat- leading to fevers

Tissue Healing

• Stage 1: Inflammation occurs
• Stage 2: Reconstructive/proliferation occurs
  • Fibroblasts synthesize collagen to make a foundation for scar tissue (granulation tissue)
  • Granulation tissue secretes cytokines and growth factors
  • Epithelial cells help make a new surface
• Stage 3: Maturation/remodeling
  • Fibroblast/myofibroblasts refine scar tissue
• 3 stages of tissue healing: primary intention, secondary intention, tertiary intention
• Healed primary intention scar ends up as a hairline scar
• Healed secondary intention scar: epithelium grows over

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