Getting the amended contents of a post

Perhaps somebody could help me with a small problem I am having.

I am writing my first stab at a plugin and have a new panel on the post editor screen.

What I want to happen is when a button on my panel is pressed, I need to grab the current contents of the post – i.e. including any changes that have been made to the content.

I have tried using $post->post_content but this only returns me the value of the post on the database (i.e. without the current amendments). I have also tried using jQuery : jQuery(‘#content’).val() but this does the same.

Any advice would be most appreciated.