I would like to change the name which is displayed as the sender's name WITHIN the email message.  This name appears next to the email address.  Here is an example of what the recipient of my email will see in his message (the sender is Daniela Nittenberg, the alias email is dr.freudenberg)

Daniela Nittenberg (*** Email address is removed for privacy ***)
3:20 PM

I would like that "Daniela Nittenberg" is replaced either by DN or Dr. Freudenberg.  How can I do this ?

Thank you for your help !

DN