I don't know what peer reviewed research you'd need for saying "these glands are what are considered the chakras". I don't really know what you're asking people to prove here... I think wires have been crossed somewhere.
This page is the kind of description I was working off. I seem to remember reading somewhere that the function of these glands was originally studied by civilisations that included the idea of chakras within their cultural spirituality, thus driving their medical investigation. This was why I was of the understanding that the idea of chakras was in its basic form a scientifically reasonable idea. However reading up on this, it appears that that idea is speculative and could be a ret-con of sorts! :) Also, I enjoyed reading this thread on my searches. I have a feeling that the conversation of chakras is a far more charged/exploited concept abroad than in the uk where it's always seemed quite innocuous to me.
So basically, you're talking about the sort of thing that /u/hallucigenia already pointed out is highly questionable rather than verifiable knowledge. The relationship between chakras and glands is purely speculative rather than something we can say with high confidence to be true.
Yea, I'm conceding the point! I don't think I understood the full connotations and claims to the purpose of chakras. I'd agree with the point made in the thread I linked, that the most reasonable understanding of what they would be in reality is a mnemonic type device for use in meditation, and since effects of meditation are unquantifiable for the most part, it'd be unreasonable to claim that any supposed link between chakras and glands is anything more than a placebo effect.