TABLE 1.

Percent inhibition of forskolin-induced cAMP accumulation in BALB-D2S cells not treated or treated with a low PTX concentration^a

Cell type	% Inhibition
	−PTX	+PTX
BALB-D2S	84.3 ± 6.8	38.6 ± 4.2*
BDo-14	73.8 ± 12.2	27.8 ± 13.4*
BDi2-22	79.2 ± 2.1	63.5 ± 7.1 (NS)
BDi3-3	66.3 ± 5.7	56.5 ± 5.8 (NS)

^aCells were incubated for 20 min with no drugs, forskolin (10 μM), apomorphine (1 μM), or both apomorphine and forskolin, with or without PTX pretreatment (10 ng/ml, 4 to 6 h). Percent inhibition of apomorphine action was calculated as described in Materials and Methods. The data are expressed as mean ± SEM of four independent experiments (n = 4) and were analyzed by repeated-measures analysis of variance with Bonferroni multiple comparison posttest (*, P < 0.05; (NS), not significant; PTX treatment compared to no PTX treatment). In all clones, basal and forskolin-induced cAMP levels were not significantly different from levels in nontransfected BALB-D2S cells. BALB-D2S cells, parent cell line; BDo-14, BALB-D2S cells expressing G_o-PTX; BDi2-22, cells expressing G_i2-PTX; BDi3-3, cells expressing G_i3-PTX.