Attention: When you forward a notification to another user via E-mail, you are simply asking that user to respond to the notification on your behalf. Note that you still maintain ownership of the notification. If you want to transfer the notification and ownership of the notification to another user, you can only do so from the Notifications web pages. See: Viewing Notifications from a Web Browser.
To Respond to a Plain Text E-mail Notification Using Direct Response
To Respond to an HTML E-mail Notification
To Respond to a Plain Text E-mail Notification with an HTML Attachment