An endogenous ligand for phencyclidine receptors: isolated from human brains

Using preparative HPLC, Sephadex G-25 and analytic HPLC, we obtained an active peak inhibiting (3H) PCP receptor binding, with a molecular weight of 3,000 daltons. Another isolation process included acetic acid extraction, Toyopearl HW gel filtration, Sephadex G-10 chromatography and analytic HPLC. An active peak was also observed, which was consistent with that from the first isolation process.