Table 1.
Effects of various factors on the transport of samples. EIPA, 5-(N-ethyl-N-isopropyl) amiloride.
| Factors | Apical Side (0.4 mL) |
Basal Side (1.0 mL) |
Temperature (°C) |
Transport Time (h) |
|---|---|---|---|---|
| Transport | F-PM/F-PG 1 (50 μg/mL) | HBSS | 37 | 0.5, 1, 2, 4 |
| Efflux | HBSS | F-PM/F-PG (50 μg/mL) |
37 | 0.5, 1, 2, 4 |
| Concentration | F-PM/F-PG (50,100,200,400,800 μg/mL) |
HBSS | 37 | 2 |
| Temperature | F-PM/F-PG (50 μg/mL) | HBSS | 4/37 | 2 |
| Inhibitors 2 | inhibitors for 1 h (remove) F-PM/F-PG (50 μg/mL) |
HBSS | 37 | 2 |
| Transferrin | chlorpromazine or dynasore for 1 h FITC-transferrin (10 μg/mL) |
HBSS | 37 | 2 |
| Dextran | EIPA for 1 h (remove) FITC-dextran (10 μg/mL) |
HBSS | 37 | 2 |
| Absorption enhancer | 0.25% CS (pH = 6.5) and F-PM/F-PG (50μg/mL) 3 | HBSS | 37 | 2 |
| Permeability | sodium fluorescein (10 μg/mL) | HBSS | 37 | 0.5, 1, 2, 3, 4 |
1 All sample solutions were prepared with HBSS. 2 For the investigation of the inhibitors, the cell monolayers were incubated with HBSS solution containing 0.4 mL of inhibitors (as shown in Table 2, including endocytosis inhibitors and intracellular transport inhibitors) for 1 h. After the incubation, the inhibitor was removed, and 0.4 mL of sample solution were added to the apical side. 3 Zero-point-four milliliters of a 0.25% CS (pH = 6.5) solution containing FITC polymannuronic acid (F-PM) or F-polyguluronic acid (PG) (the final concentration of F-PM or F-PG was 50 μg/mL).