Human erythrocytes have binding sites for beta-endorphin.
Monoiodinated human beta-endorphin was found to bind specifically to human erythrocytes. Unlabeled beta-endorphin and beta-endorphin inhibited binding, but (-)naloxone, [D-Ala2, D-Leu5]-enkephalin, and leu- and met-enkephalin did not. Immunoelectron microscopy, using rabbit anti-beta-endorphin antibody, an antirabbit IgG secondary antibody, and complexed horseradish peroxidase, revealed that at low concentrations beta-endorphin binds to the cell surface. Electron spin resonance spectroscopy showed no effect of beta-endorphin on membrane fluidity. This receptor does not appear to conform to the characteristics of an opiate receptor.
Simpkins
C O
CO
Chenet
B P
BP
Kang
Y H
YH
Mazorow
D L
DL
Millar
D B
DB
Hollis
V W
VW
D004912:Erythrocytes / Q000378:metabolism*; D006801:Humans; D008560:Membrane Fluidity; D011957:Receptors, Opioid / Q000378:metabolism*; D001615:beta-Endorphin / Q000378:metabolism*
D011957:Receptors, Opioid; D001615:beta-Endorphin