TABLE 1

Inhibitory effects of various compounds on [3H]estrone-3-sulfate uptake by T-47D cells

Cultured T-47D cells were incubated at 37°C for 10 min in medium containing [3H]estrone-3-sulfate (7.1 nM) with or without (control) an inhibitor at the indicated final concentration. Transporter-mediated uptake was calculated by subtracting the uptake in the presence of excess estrone-3-sulfate (1 mM) from the total uptake. Uptake was expressed as percentage of the control uptake. Each value represents the mean ± S.E.M. (n = 4).


Inhibitor

Concentration

Percentage of Control
μM
Control 100.0 ± 4.7
Estrone-3-sulfate 5 34.7 ± 4.3*
50 6.6 ± 0.9*
DHEAS 5 66.4 ± 5.7*
50 27.0 ± 7.6*
Estradiol-17β-glucuronide 5 73.8 ± 8.7
50 90.4 ± 11.5
Estrone 5 78.8 ± 3.3*
50 64.8 ± 7.5*
Dehydroepiandrosterone 5 75.6 ± 3.8*
50 44.8 ± 8.0*
Estradiol 5 76.9 ± 4.8*
50 45.7 ± 5.3*
Sulfobromophthalein 100 18.9 ± 2.8*
1000 14.2 ± 1.2*
Taurocholic acid 100 69.3 ± 2.7*
1000 24.1 ± 2.3*
Probenecid 100 103.2 ± 10.2
1000 79.1 ± 3.8*
Benzylpenicillin 100 83.2 ± 2.0*
1000 75.9 ± 10.5
Salicylate 100 94.9 ± 6.0
1000 82.7 ± 7.3
p-Aminohippuric acid 100 87.8 ± 1.5
1000 112.7 ± 18.6
Tetraethylammonium 100 87.4 ± 1.5*
1000 112.7 ± 18.6
Control (DMSO 1%) 100.0 ± 9.7
Cyclosporin A (DMSO 1%) 10 112.2 ± 8.3
100 90.3 ± 3.7
Digoxin (DMSO 1%) 100 90.3 ± 3.5

1000
94.8 ± 4.4
  • * P < 0.05, compared with control (Student's t test).