Table 1

Influence of bicarbonate and pH gradients on [3H]AG uptake in cLPM vesicles

AG Uptake (pmol/mg of protein)
20 s4 min60 min
Bicarbonate gradient1-a
 Control0.82  ± 0.040.82  ± 0.040.81  ± 0.02
 Treated0.82  ± 0.030.83  ± 0.030.82  ± 0.02
Inside/outside pH1-b
 7.4/6.00.92  ± 0.140.93  ± 0.160.97  ± 0.15
 7.4/7.40.91  ± 0.170.94  ± 0.180.95  ± 0.17
 7.4/8.00.90  ± 0.150.91  ± 0.150.89  ± 0.13

Data are expressed as mean ± S.D. (n = 3 in triplicate).

  • ↵1-a  Rat cLPM vesicles were preloaded with standard membrane suspension buffer and 100 mM KHCO3. Standard incubation buffer contained 100 mM KHCO3 (control) or 100 mM potassium gluconate (treated). Stop solution contained 250 mM sucrose, 10 mM Hepes/Tris (pH 7.4), 0.2 mM CaCl2, and 100 mM potassium gluconate.

  • ↵1-b  Rat cLPM vesicles were preloaded with standard membrane suspension buffer (pH 7.4) and incubated with standard incubation buffer at pH 6.0, 7.4, or 8.0.