title: Beta-Endorphin. Interaction of synthetic analogs having different chain lengths with morphine and enkephalin receptors in rat brain membranes.
abstract: Human beta-endorphin analogs with various chain lengths have been investigated for their potency in displacing tritiated dihydromorphine and Leu-enkephalin binding in rat brain membrane preparations. It was found that the reduction of chain length from residues 1-31 to 1-5 led to a gradual loss of preference for the morphined receptor. In addition, the extension of the chain length of the Met-ekephalin segment to the COOH-terminal glutamic acid modified the binding of the NH2-terminal sequence to the enkephalin receptor. The fact that camel beta-endorphin is more potent in displacing the two tritiated primary ligands than the human hormone is also reported herein.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D004723:Endorphins / Q000378:metabolism*; D006801:Humans; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000378:metabolism*; D013045:Species Specificity; D013329:Structure-Activity Relationship; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D011957:Receptors, Opioid; D001615:beta-Endorphin