Fig. 3.

Inhibitory effect of corticosterone (1 and 300 μM) and clonidine (50 μM) on [³H]-MPP⁺ apical uptake by control and HG Caco-2. Confluent Caco-2 monolayers were preincubated at 37 °C in the presence of H₂O (control) or the test compounds and then incubated with 200 nM [³H]-MPP⁺ for 5 min. Each value represents the mean ± SEM of the triplicates of two independent experiments (n = 6). * P < 0.05 (significant increase and decrease)