Reversing Particle Edits

I have noticed that as soon as I put the 3D View Editor in Particle Edit mode the Emission settings in “Properties Editor => Particle” grays out and it is no longer possible to make changes there. Is there a way to undo all the edits done in the Particle Edit mode and get back to a point where Emission settings can be edited again without deleting the entire particle system?

I first noticed this after combing hair.