I need To solutions for loading drop down list data..?

I am developing a web application using MVC. I have some list of data this data would populate into the dropdown list. This data will be used in several places in project this reason i am getting data when I first login. Here i am able to add the data to a llist but it not reflect immediately. How can I overcome this problem?. basically each controller extends base controller. The base controller develops by our self basic upon our requirement.