Functional expression of a proton-coupled organic cation (H+/OC) antiporter in human brain capillary endothelial cell line hCMEC/D3, a human blood–brain barrier model

Table 2 Effects of metabolic inhibitors (rotenone and sodium azide), protonophore (FCCP), sodium replacement and change in membrane potential by valinomycin on diphenhydramine uptake by hCMEC/D3 cells

Uptake of diphenhydramine (30 μM) was measured at 37°C for 15 sec in the absence or presence of metabolic inhibitors (25 μM rotenone and 0.1% sodium azide) and a protonophore (10 μM p- FCCP) and 10 µM valinomycin. The uptake was also measured in sodium-free incubation buffer (Na⁺ was replaced with N-methylglucamine). ^a) Rotenone was dissolved in the transport buffer containing 0.25% ethanol. ^b) 25 µM rotenone and 0.1% sodium azide were added to the transport buffer without 10 mM D-glucose to reduce metabolic energy. ^c) The cells were preincubated with the transport buffer containing 10 μM valinomycin for 10 min. Valinomycin was dissolved in the transport buffer containing 0.22% ethanol. Each study was performed in parallel with a control containing the corresponding ethanol concentration. Each value represents the mean as % of control ± S.E. (n = 3). **p<0.01 and **p<0.001 vs control.

ISSN: 2045-8118