Binding studies of L-Prolyl-L-leucyl-glycinamide (PLG), a novel antiparkinsonian agent, in normal human brain

In an attempt to elucidate the mechanism subserving the potential antiparkinsonian properties of L-Prolyl-L-leucyl-glycinamide (PLG) in humans, we used a radioligand binding assay to identify specific binding sites of PLG in normal human brain. 3H-PLG bound to crude membrane homogenates obtained from human striatum with high affinity and in a saturable manner (Bmax = 10.04 ± 0.82 fmoles/mg−1 protein and KD = 3.60 ± 0.43 nM). The regional …