TABLE 1:
Altered NHE3 transport activity of Caco-2/bbe cells expressing Ad-HA-NHE3- S719A in response to inhibitory or stimulatory agents compared with NHE3-WT activity.
| Na+/H+ exchange activity | ||
|---|---|---|
| Inhibitor/activator | NHE3-WT | NHE3-S719A |
| Basal | Normal | Reduced |
| DMAT | Inhibits | Lost effects |
| Wortmannin | Inhibits | Lost effects |
| AKTi VIII | Inhibits | Lost effects |
| LPA | Stimulates | Lost effect |
| Forskolin | Inhibits | Inhibits |
| Hyperosmolarity | Inhibits | Inhibits |
| Carbachol | Inhibits | Lost effects |
| A23187 | Inhibits | Lost effects |
NHE3-S719A mutant lost part of basal NHE3 activity, as well as calcium and LPA effects on NHE3 activity. Normal regulation: forskolin and hyperosmolarity. Altered regulation: basal, DMAT, wortmannin, AKTi-VIII, carbachol, A23187, LPA.