Abstract: A novel, isolated EDG receptor that upon activation results in increased induction of IL-8 or NF-&kgr;B. Preferably, the EDG receptor is a human EDG-4 receptor, which has an amino acid sequence shown in FIGS. 16A and 16B, or a variant of these sequences having at least 91% sequence identity.

Abstract: Cell lines that stably incorporate human D.sub.4 receptor-encoding DNA are provided which are particularly useful in procedures for screening compounds for potential anti-psychotic activity.

Abstract: Described herein are D4 receptor-selective compounds of the general formula: ##STR1## wherein: A and B are independently selected, substituted or unsubstituted, unsaturated 5- or 6-membered, homo- or heterocyclic rings;X.sub.1 is selected from O, S, SO, SO.sub.2, CH.sub.2, C.dbd.O, CH--OH, CH--N(C.sub.1-4 alkyl).sub.2, C.dbd.CHCl, and C.dbd.CHCN;X.sub.2 --- is selected from N.dbd., CH.sub.2 --, CH.dbd. and C(O)--;n is 1 or 2;R.sub.1 is selected from H and the .alpha.-carbon side chain of an amino acid;R.sub.2 and R.sub.3 are selected independently from H, OH, --NH.sub.2, --C(O)NH.sub.2 .dbd.O, .dbd.S,halo,cyano, C.sub.1-9 alkyl, C.sub.1-9 alkoxy, C.sub.1-4 alkylS--, C.sub.1-4 alkylSO--, C.sub.1-4 alkylSO.sub.2 --, phenoxy, benzyloxy and piperonyloxy; andH* is in either the R- or the S-configuration,and acid addition salts, solvates and hydrates thereof.