I have read this paper over also. Very interesting paper. I don't know if the binding activity has been reported yet but I might have looked that up once, I will check through my literature sometime this week. I think I have found binding affinity for tryptamine and phenethylamine but can't remember.

I think its important that people read this to get a fresh view on the latest research to see that theres more to endogenous DMT then the pineal gland hypothesis, which I still see no evidence for.

Have the trace amine receptors been cloned? That could greatly facilitate research since they are membrane bound they need to be expressed in some liposome like membrane.