|
Ligand |
mu receptor |
kappa receptor |
delta receptor |
|
Morphine |
Agonist (strong) |
Agonist (weak) |
Agonist (weak) |
|
Naloxone |
Antagonists (strong) |
Antagonist (medium) |
Antagonists (weak) |
|
Naltrexone |
Antagonist (strong) |
Antagonist (strong) |
Antagonist (weak) |
NOTE: Naloxone is a competitive antagonist at mu-opioid receptors, which are the primary sites of action for opioid analgesics. By blocking these receptors, naloxone can reverse the effects of opioid overdose.
Reference:
1. Essentials of Medical Pharmacology, KD Tripathi, 8th edition, P. No. 508