| Regulated secretion of HCl by gastric oxyntic cells involves an elaborate surface remodeling as cytoplasmic vesicles, called tubulovesicles containing H,K-ATPase, are recruited to the apical surface upon secretagogue stimulation. Cessation of acid secretion is accompanied by the reestablishment of tubulovesicles. It is believed that the trafficking of the H, K-ATPase may be mediated by cytoskeletal elements such as microtubules. In this study we have identified the presence of microtubule motor proteins, dynein and kinesin, in oxyntic cells. In addition, we have also demonstrated the presence of two components of the dynactin complex, p150Glued and p50. We have also immunolocalized p150Glued and p50 in oxyntic cells. Our studies suggest that microtubule-dependent motor proteins together with their activator-receptor complexes may play a role in the trafficking of the gastric H,KATPase. |
