The opioid peptides and their receptors.
D000818:Animals; D004594:Electrophysiology; D004745:Enkephalins / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D011957:Receptors, Opioid / Q000502:physiology*
D004745:Enkephalins; D011957:Receptors, Opioid