Assigning a key resource from code-behind

hi,

I need to replicate in code-behind the assignment for the Header (LABEL):

XAML:

<Label Content="{Resx OrExpander_ActionsSave}" Name="Guardar"  Style="{StaticResource ActionLabelStyle}"

Code-behind:

I've got the assignment for the style:

Dim estilet As System.Windows.Style = Me.FindResource("ActionLabelStyle")

  Dim label2 As New Label

label2.Style = estilet

But how can I assign the key named "OrExpander_ActionsSave"?

TIA,

Primary platform is Windows 7 Ultimate 64 bit along with VS 2012/Sql2k8 for WPF/SilverLight projects.