Opiate receptor binding is regulated by guanine nucleotides differentially for agonists and antagonists. Guanosine-5′-triphosphate (GTP), its stable analogue guanyl-5′-yl-imidodiphosphate (Gpp(NH)p) and GDP inhibit binding of the 3H-agonists dihydromorphine, etorphine and enkephalins but not the 3H-antagonists naloxone or diprenorphine. GMP, ATP, ADP and AMP fail to alter either agonist or antagonist binding. Effects are more pronounced in the presence than in the absence of sodium.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Pharmacology, Toxicology and Pharmaceutics(all)