Get gridPanel columns at server side

[Fla]

Hi again :)
Is there a way to retrieve at server side the columns list for a gridpanel?
I've tried to get the grid using

var grid = this.GetCmp<GridPanel>(myGridName);

and it runs, however all properties of the object are empty or null...
For example: grid.Store is always null and so grid.Columns

Note: I need these info in an action called from a button click.

Regards,
Fla