Opioid receptors MEDECIN ABONNE

Definition

Opioid receptors are receptors located in the cell membrane coupled with G proteins having as ligand an opioid (derived from the word opium).

Description

There are 4 subtypes of opioid receptors:

  • Delta (δ)
  • Kappa (κ)
  • Mu (μ)
  • Nociceptive receptors

Delta receiver

Location

  • In the brain

Function

  • Analgesia
  • Antidepressant effects
  • Physical dependence

Kappa receiver

Location

  • In the brain
  • In the spinal cord in the gelatinous substance

Function

  • Spinal cord analgesia
  • Sedation
  • Myosis
  • Inhibition of ADH hormone release

Mu Receiver

Location

  • In the brain,
  • In the spinal cord at the level of the gelatinous substance
  • In the digestive system

Function

Depending on the subtype of μ receptors:

  • Supraspinal analgesia
  • Physical dependence
  • Respiratory depression
  • Myosis
  • Euphoria
  • Reduced motility of the gastrointestinal tract
  • Physical dependence
  • Nociceptive receptor

Location

  • In the brain,
  • In the spinal cord

Function

  • Anxiety
  • Depression
  • Appetite
  • Development of tolerance to μ-receptor agonists

 

 

Post operative chronic pain