Erowid References Database
|
van Ree, JM, Witter A, Leysen JE.
“Interaction of Des-Tyrosine-y-Endorphin (DTyE, beta-LPH62-77) With Neuroleptic Binding Sites in Various Areas of Rat Brain”.
Eur.J.Pharmacol.. 1978;52(3-4):411-13.
|
|
Abstract
The interaction of des-tyrosine-y-endorphin (DTyE, beta-LPH62-77 ) and related fragments with the in vitro binding of centrally acting drugs was studied. Methods LSD, fentanyl, naloxone, muscimol, dexetimide and diazepam binding assays were performed using a technique similar to that used for the neuroleptic drugs. A microsomal fraction from rat brain regions was incubated in the presence of 3H-ligand (2-4 nM) and various concentrations of beta-LPH 61-76 (alpha-endorphin), beta-LPH 62-76 (DT alphaE), beta-LPH62-77 (DTyE0, beta-LPH78-91, ACTH4-10 (beta-LPH47-53) and ACTH4-10 (D-PHe) (all Organon). Results None of the 6 peptides tested were able to displace 3H-haloperidol or 3H-spiperone from their stereospecific binding sites in membrane preparations of rat striatum or frontal cortex, respectively, or the 3H-spiperone binding in the accumbens area in the presence of both R43448 and 5,6-dihydroxy-2N,N-dipropyl-aminotetraline. The endorphin fragments did not inhibit d 3H-LSD and 3H-diazepam binding in cerebral cortex and frontal cortex fractions, respectively. Fentanyl binding in the forebrain was inhibited by alpha-endorphin in a dose-dependent manner (IC56: 2 X 10^-7 M), less effectively by beta-LPH18-41 and ACTH4-10 (D-Phe^7) and was not inhibited by the otherendorphin fragments. Similar results were obtained with naloxone binding. There was no interaction of DTyE with 3H-muscinol and 3H-dexetimide binding in membrane preparations of rat cerebellum or rat striatum, respectively. The peptides did not markedly interfere with the ligand binding to neuroleptic sites at 0 degrees or in the presence of bacitracin (100 mcg/ml).
|
| # |
| Submit Comment |
|
[
Cite HTML ]
