Pharmacologie: Partie 4: Physiologie et pharmacologie de la douleur Flashcards
What is douleur as defined by the IASP?
Une expérience sensorielle et émotionnelle désagréable associée ou ressemblant à celle associée à une lésion tissulaire réelle ou potentielle.
What are the 6 concepts clé?
1. pain is always a personal experience influenced by biological, psychological or social factors
2. pain and nociception are different phenomena but pain can not be completely separated from the activity of sensory neurons
3. people learn about pain thanks to their life experience
4. a person’s experience of pain must be respected
5. although pain generally plays an adaptive role, it can have adverse effects on social and psychological function and well-being.
6. verbal description is only one of the things that is used to express pain… not being able to communicate DOES NOT mean that they don’t feel pain
How prevalent is chronic pain?
- 20% of the population
- this number is rising with rising population ages
- atherosclerosis, diabetes, and cancer are some of these reasons for increasing
What is the purpose of acute pain?
Signal d’alarme –> qqch menace notre intégrité
What is the purpose of chronic pain?
Inutile… danger is usually gone –> alarm system that stays on
(mauvaise adaptation qui a des impacts fonctionnels majeurs)
What is nociception?
L’ensemble des phénomènes permettant l’intégration au CNS d’un stimulus douloureux via l’activation des nocicepteurs cutanés, musculaires et articulaires
What is douleur?
Sensation désagréable et subjective dans une partie du corps suite à un stimulus nociceptif
What is allodynia?
Allodynia is a condition in which pain is caused by a stimulus that does not normally elicit pain. For example, bad sunburn can cause temporary allodynia, and touching sunburned skin, or running cold or warm water over sunburned skin can be very painful
What is hyperalgesia?
Hyperalgesia is a condition in which you experience an enhanced sensitivity to pain. This is caused by specific nerve receptors in your body becoming more sensitive. Hyperalgesia can develop due to tissue or nerve injury as part of a surgery or procedure.
What are the three kinds of pain?
- Nociceptive pain is a type of pain caused by damage to body tissue. Nociceptive pain feels sharp, aching, or throbbing.
- Neuropathic pain is pain caused by damage or disease affecting the somatosensory nervous system
- Nociplastic pain is pain that arises from altered nociception despite no clear evidence of actual or threatened tissue damage causing the activation of peripheral nociceptors or evidence for disease or lesion of the somatosensory system causing the pain
What are the functions of the somatosensorial system?
- Touch
- Perception
- Temperature
- Nociception
What are the steps of pain transmission?
- Transduction
- Transmission
- Modulation
- Perception
What are the mechanisms of pain reception en périphérie?
When nociceptors are activated:
- Signal is transformed (transduction: chemical signal)
- Activates multiple reactions:
- Inflammation –> cellular and chemical
- Local production of NTs
How are messages transmitted?
Aβ fibres: vibration, movement, light touch
Aδ fibres: temperature and pain (FIRST PAIN… sharp pain)
C fibres: pain (SECOND PAIN… slow, lasting and spread out)
- Aδ and C fibres: transport message to colonne dorsale de la moelle épinaire
- Important network of neurons that can modulate a signal:
- Increase
- Decrease
How does perception happen?
Message goes to the brain where perception happens
What 5 structures are implicated in perception?
- Thalamus +++
- Primary somatosensorial cortex (parietal lobe)
- Secondary somatosensorial cortex (parietal operculum)
- Insular cortex (below frontal and temporal cortexes)
- Anterior cingulate cortex (below corpus callosum)
