Abstract
[3H]-(−)-bremazocine was displaced from guinea-pig brain membrane homogenates by three compounds having different specificity to opiate receptor subpopulations. A three site receptor model showed the best fit of the calculated to the measured value for the opiate mu (DAla2, MePhe4, Gly(ol)5-enkephalin) and the delta specific compound (DAla2, DLeu5-enkephalin). Computer modelling of data from displacement curves with the opiate kappa specific compound U-50.488H favored a two site receptor model.