Recombinant HEK293 cell line expressing rat PDE7A (phosphodiesterase 7A, accession number NM_031080). ; N-terminal FLAG-tagged rat PDE7A has been stably expressed in a human embryonic kidney (HEK293) cell line and its expression was confirmed by Western blotting. The regulation of intracellular level of cAMP by rat PDE7A in rat PDE7A stably-expressed HEK293 cells was characterized by a cell-based reporter assay using pCRE-luc reporter vector. pCRE-luc contains a luciferase gene that is under the control of the cAMP response element (CRE). When cells transiently transfected with pCRE-luc reporter were activated by forskolin, the level of cAMP was upregulated in parental HEK293 cells inducing the expression of luciferase reporter, whereas rat PDE7A-HEK293 cells showed reduction in the level of cAMP, resulting in lowered levels of luciferase expression. Inhibition of PDE7A activity by BRL 50481, a PDE7A inhibitor, restored the cAMP level, resulting in higher luciferase activity.