Figure 5.

CRE-SPAP production in CHO-A1 cells in response to APrEA-X-BY630 (A and D), APEA-X-BY630 (B and E), ADOEA-X-BY630 (C and F) in the presence and absence of 30 nM DPCPX (A, B and C) and 10 nM DPCPX (D, E and F). The cells in D, E and F were incubated with PTX (100 ng·mL⁻¹) for 24 h before experimentation. Bars show basal CRE-SPAP production, that in response to 3 µM forskolin and that in response to either 30 nM or 10 nM DPCPX in the presence of 3 µM forskolin. Data points are mean ± SEM from triplicate values from a single experiment. These separate experiments are representative of (A) 8, (B) 8, (C) 6, (D) 6, (E) 6 and (F) 6 separate experiments. ADOEA, N⁶-(8-amino-3,6-dioxaoctyl)-5′-ethylamino-5′-oxo-5′-deoxyadenosine; APEA, N⁶-(5-aminopentyl)-5′-ethylamino-5′-oxo-5′-deoxyadenosine; APrEA, N⁶-(3-aminopropyl)-5′-ethylamino-5′-oxo-5′-deoxyadenosine; CHO, Chinese hamster ovary; CRE-SPAP, cyclic AMP response element-secreted placental alkaline phosphatase; DPCPX, 8-cyclopentyl-1,3-dipropylxanthine; NECA, 5′ (N-ethylcarboxamido)adenosine; PTX, Pertussis toxin; X, 6-aminohexanoyl.