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

Monoclonal antibodies generated against multiple antigenic peptides of the N-terminal sequence ((LVP)-L-3-SARAELQSSPLV(17)) of the cloned delta opioid receptor immunoprecipitated a 58 kDa protein from CHAPS-solubilized NG108- 15 membranes. The immunoprecipitates bound [H-3]DPDPE - but not [H-3]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 PGE(1)-stimu lated cAMP levels, and mimicked the effect of agonists manifest in a compen satory increase in cAMP formation. The antibody a ill be potentially useful in the analysis of functional epitopes on the delta opioid receptor. (C) 1 999 Federation of European Biochemical Societies.