How does inflammation change blood flow?
It increases blood flow to sites of injury and delivers nutrients and O2.
What happens during inflammation?
EMERGENCY
- Exudate carries antibodies and protective substances into affected area to neutralise harmful agents.
- It also carries toxins away via lymphatic drainage (oedema) to local lymph nodes to stimulate an immune response.
- Limits the spread of harmful agnts by encapsulating the injury (abscess walls, fibrin mesh of clot)
After emergency inflammatory response, what gets rid of the exudate?
Hydrolases digest the inflmmatory exudate
Who was John Hunter and what did he observe about inflammation?
The first to observe that inflammation is not a disease but a response to tissue injury
John Hunter lived from 1828 to 1793.
Define inflammation.
- The body’s natural response to injury and infection
- Unpleasant transient coordinated emergency response
- The central basis of many diseases
Inflammation is crucial for healing and defense mechanisms.
What are the four cardinal signs of inflammation?
- Redness (rubor)
- Heat (calor)
- Swelling (tumor)
- Pain (dolor)
These signs indicate the presence of inflammation in tissues.
What is the purpose of inflammation?
- Delivers nutrients and O2 to injured sites
- Generates exudate carrying antibodies and protective substances
- Carries toxins away via lymphatic drainage
These functions help neutralize harmful agents and stimulate the immune response.
What are the 3 causes of acute inflammation
- Complete resolution: sucessful healing
- Abscess (pus-forming), scar formation
- Chronic healing
Chronic inflammation can lead to various diseases and health issues.
What is the first step in the process of acute inflammation?
- Capillary widening (vasodilation)
- Increasing permeability
- Attraction of leukocytes
These steps are crucial for initiating the inflammatory response.
What are cell-derived factors in inflammation?
- Bioactive peptides
- Damage associated molecular patterns (DAMPs)
- Pathogen associated molecular patterns (PAMPs)
These factors help activate acute inflammation by binding to Pattern Recognition Receptors (PRR).
Which two cell types are key to detecting cell-derived factors?
- Mast cells
- Macrophages
These cells respond to damage signals and initiate the inflammatory process.
What mediators are involved in the inflammatory response?
- Histamine
- Proteases (e.g., tryptases)
- Lipid signals
- Cytokines (e.g., TNF)
These mediators drive vasodilation and increased permeability.
Describe the process of vasodilation.
- Smooth muscle cells relax
- Arteriole lumen increases in diameter
- Increased blood flow into capillary network
This process leads to redness and heat in tissues.
What causes oedema?
- Vasopermeability
- Vasodilation
Oedema results from fluid build-up in tissues, leading to swelling.
What can exudate lead to?
- Formation of edema
- Blisters
- Blockage of tubes (e.g., airway constriction)
- Effusions (e.g., pleural effusion)
Exudate is a fluid that accumulates in tissues during inflammation.
What progresses acute inflammation?
- Cell-derived mediators
- Control of blood vessel function
- Induction of vasopermeability and vasodilation
These factors contribute to the inflammatory response and symptoms.
What are vasoactive amines and their role in inflammation?
- Histamine
- Vasodilation
- Vasopermeability
- Neutrophil recruitment
Vasoactive amines are released during degranulation of mast cells and basophils.
What is the role of tryptases in inflammation?
- Cleave protease-activated receptors (PARs)
- Induce vasopermeability
- Promote vasodilation
Tryptases are derived from mast cells and play a significant role in the inflammatory process.
What are the inflammatory signaling cascades?
- Coagulation
- Fibrinolytic
- Kinin
- Complement
These cascades have potent vasoactive effects and are crucial for the inflammatory response.
What activates the coagulation pathway?
Damaged endothelial cells (e.g., tissue factor)
This activation leads to the cleavage of prothrombin into thrombin and fibrinogen into fibrin.
From circulating mediators, what are the two inflammatory signalling cascades involved in blood clotting?
Coagulation and fibrinolytic
From circulating mediators, what are the two inflammatory signalling cascades involved in blood flow?
Kinin and complement
