Evidence for multiple opioid receptors in the human posterior pituitary.
The distribution and quantification of opioid receptor types in post-mortem human pituitary cryostat sections was determined by quantitative in vitro receptor autoradiography. Highly specific radioligands were used for each opioid receptor type i.e. [125l]-FK-33-824 for mu-opioid sites, [125l][D.Ala2]-Deltorphin-l for delta-opioid sites and 3H-U69,593 for kappa-opioid sites. None of the five specimens tested exhibited any labeling in the anterior lobe of the pituitary for the three radioligands. As for the posterior pituitary, all 5 specimens contained both mu and kappa-opioid binding sites whereas none of them showed delta-binding sites. The presence of both mu- and kappa-opioid binding sites in the human posterior pituitary contrasts with previous findings in the rat where only kappa-sites have been found. The present study could contribute to understanding of the functional action of opioids in the human pituitary.
Jordan
D
D
Unité de Recherche de Neuroendocrinologie Morphofonctionnelle, INSERUM U.378, Université de Bordeaux ll, France.
Tafani
J A
JA
Ries
C
C
Zajac
J M
JM
Simonnet
G
G
Martin
D
D
Kopp
N
N
Allard
M
M
D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; D000328:Adult; D044482:Benzeneacetamides; D001665:Binding Sites; D001667:Binding, Competitive; D002102:Cadaver; D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin / Q000378:metabolism; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D004745:Enkephalins / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009294:Narcotics / Q000378:metabolism; D009842:Oligopeptides / Q000494:pharmacology; D010904:Pituitary Gland, Posterior / Q000378:metabolism*; D011759:Pyrrolidines / Q000378:metabolism; D011957:Receptors, Opioid / Q000378:metabolism*; D014018:Tissue Distribution
D044482:Benzeneacetamides; D004745:Enkephalins; D009294:Narcotics; D009842:Oligopeptides; D011759:Pyrrolidines; D011957:Receptors, Opioid; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; C060208:deltorphin I, Ala(2)-; D005405:D-Ala(2),MePhe(4),Met(0)-ol-enkephalin; D019900:3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer; C045444:U 69593