Opiate receptors in the pigeon optic tectum.
D000818:Animals; D010856:Columbidae; D004745:Enkephalins / Q000378:metabolism; D005048:Etorphine / Q000378:metabolism; D007700:Kinetics; D011957:Receptors, Opioid / Q000502:physiology*; D013477:Superior Colliculi / Q000502:physiology*
D004745:Enkephalins; D011957:Receptors, Opioid; D005048:Etorphine