Monoclonal antibody to the δ opioid receptor acts as an agonist in dual regulation of adenylate cyclase in NG108‐15 cells

Abstract
Monoclonal antibodies generated against multiple antigenic peptides of the N‐terminal sequence (3LVPSARAELQSSPLV17) of the cloned δ opioid receptor immunoprecipitated a 58 kDa protein from CHAPS‐solubilized NG108‐15 membranes. The immunoprecipitates bound [3H]DPDPE – but not [3H]DAMGO – with a K d of 6.4 nM and a B max of 75 pM. Western blot analysis revealed a distinct band of 58 kDa. The antibodies inhibited basal and PGE1‐stimulated cAMP levels, and mimicked the effect of agonists manifest in a compensatory increase in cAMP formation. The antibody will be potentially useful in the analysis of functional epitopes on the δ opioid receptor.