C fragment of lipotropin has a high affinity for brain opiate receptors.

Amino Acid Sequence Binding, Competitive Brain/metabolism Morphine Derivatives/metabolism Naloxone/metabolism Nerve Tissue Proteins/metabolism Opium Peptides/metabolism Potassium/pharmacology Receptors, Drug/drug effects Sodium/pharmacology Structure-Activity Relationship beta-Lipotropin/metabolism

Morphine Derivatives Nerve Tissue Proteins Peptides Receptors, Drug Naloxone Opium beta-Lipotropin Sodium Potassium