US-OR-MINUS)-1-AMINO-1,3-CYCLOPENTANEDICARBOXYLATE (TRANS-ACPD) STIMULATES CAMP ACCUMULATION IN RAT CEREBRAL CORTICAL SLICES BUT NOT IN GLIAL OR NEURONAL CELL-CULTURES

Recent cloning experiments indicate that multiple metabotropic recepto rs for excitatory amino acids (EAAs) exist, which are coupled to adeny late cyclase. Trans-(+/-)-1-amino-1,3-cyclopentanedicarboxylate (trans -ACPD) is a selective agonist of metabotropic receptors for EAAs. One of the effects of trans-ACPD is stimulation of cAMP accumulation. In t he present experiments, cAMP accumulation was measured using a [H-3]ad enine-prelabelling technique. It has been found that trans-ACPD was ab le to induce significant stimulation of cAMP accumulation in rat cereb ral cortical slices, with ED50 of 47.8 muM, which value is similar to that described earlier for hippocampal slices. However, trans-ACPD had no effect on cAMP accumulation either in primary neuronal or glial ce ll cultures. The reason for the lack of effects of trans-ACPD on cAMP accumulation in primary cultures from glial cells and neurons is discu ssed.