Beth Levant
blevant@kumc.edu
We did some binding studies with 3H-pargyline, the only radiolabeled MAOI we were able to obtain from a commercial source. �Initial results suggested that it was labeling MAO. �Since pargyline is an irreversible MAOI and MQB is reversible, we tried pretreating the membranes with pargyline to block MAO and then proceeding with the binding assay. �Initial results suggested that this approach might work. �Unfortunately, 3H-pargyline was discontinued and we were not able to complete the experiments.
Ideally, I would like to use this approach with a radioligand with higher affinity for the MQB site, perhaps Ro 41-1049. �Roche radiolabeled the compound a number of years ago and used it to map the distribution of MAO-A in the CNS but it has never been available commercially. �I believe that if we pretreat the membranes with clorgyline to block MAO-A, we should be able to label the MQB site. �However, these experiments will have to to wait until I can afford a custom-synthesized radioligand.