I've been trying to analyze the effects of oxidative damage on RNA, and it seemed like putting hydrogen peroxide in with blood samples would do the trick. Yet, when its extracted and the gels are run, they look essentially identical to the samples without any peroxide.

 

I'm stumped :| does anyone know anything else I could try?

Are you getting roughly similar concentrations? I'm very much speculating here as my experience with RNA extraction is limited, but is it possible that maybe your extraction method is excluding any damaged RNA from your final sample?

That doesn't seem to be the case - all the bands are of basically equal brightness