8-Opioids Flashcards
Opioids Involved In
Pain (nociception)
GI function
Respiration
Response to stress (psychological homeostasis)
MOR
Mu receptor
Analgesic/antinociception
Primary receptor in pain pathway
Side Effects: Nausea sedation Respiratory depression Abuse potential Tolerance to analgesia Opioid induced hyperalgesia (heightened pain response)
DOR
Delta
Analgesia for chronic pain
Mood improvement
Side effects:
Convulsions and hyperlocomation for a few DOR agonists at high dose
Analgesia tolerance
KOR
Kappa
Analgesia/antinociception
Side Effects:
Sedation
Dysphoria
Aversion
Endogenous Opioids That Bind to MOR
Beta endorphin
Endomorphin
Endogenous morphine
Also have low affinity for DOR
Endogenous Opioids That Bind to DOR
Enkephalins
Also binds to MOR
Endogenous Opioids That Bind to KOR
Dynorphins
Also has low affinity for DOR and MOR
Antinociception
Blocking pain detection at receptor level (doesn’t reach brain)
Analgesia
State of not being able to feel pain (brain)
Beta Endorphin
Produced from pro-opiomelanocortin (POMC)
Synthesized in pituitary gland
Released in response to HYP activation (stress, pain)
Involved in many CNS processes
Low affinity for DOR
Enkaphalins
Produced from pro-enkephalin
SYnthesis is widespread (high in mesocorticolimbic- VTA, cortex, NAcc)
Involves in many CNS processes including analgesia
Also binds to MOR
Dynorphins
Produced from prodynorphin
Synthesis is widespread in brain (amygdala, HPC, NAcc, HYP)
Involved in many CNS processes including analgesia
Low affinity for DOR and MOR
