RT Journal Article
SR Electronic
T1 Differential Effects of Protein-Modifying Reagents on Receptor Binding of Opiate Agonists and Antagonists
JF Molecular Pharmacology
JO Mol Pharmacol
FD American Society for Pharmacology and Experimental Therapeutics
SP 340
OP 351
VO 11
IS 3
A1 GAVRIL W. PASTERNAK
A1 H. ALEXANDER WILSON
A1 SOLOMON H. SNYDER
YR 1975
UL http://molpharm.aspetjournals.org/content/11/3/340.abstract
AB Opiate receptor binding is enhanced by prior incubation, which removes an endogenous inhibitor of receptor binding. Protein-modifying reagents which affect sulfhydryl groups differentially influence the binding of agonists and antagonists to the opiate receptor. These reagents, including iodoacetamide, N-ethylmaleimide, mercuriacetate, mersalyl acid, p-aminophenylmercuric acetate, and p-chloromercuribenzoate, strongly inhibit [3H]dihydromorphine binding at concentrations which do not affect [3H]naloxone binding. Prior treatment with opiates protects the receptor binding from reagents. The reagents decrease the apparent number of dihydromorphine binding sites without altering their affinity, and also increase the sensitivity of agonist binding to the inhibitory effects of sodium. ACKNOWLEDGMENT The authors are grateful to Adele Snowman for her inspired technical assistance.