no, you cannot use power cms to create the email body.
You could use HTML Editor.
on the email page, add an html editor instance, use HTML Editor to design the email body in the universal Email interface, use the Dreamweaver edit tool, and add a binding for the HTML Editor instance.
when you run the page, design the email in HTMML Editor, when the page is sent, the contents of the HTML Editor should be used for the email body.