Talk:Reniculate kidney#Clarification needed

For the one and a half sentences "The reniculate structure in cetaceans and pinnipeds does not result in a greater concentrating ability. While many marine mammals can concentrate their urine beyond the concentration of sea water, ..." what specific solute(s) are meant? It doesn't seem to be sodium and chloride, as the rest of the paragraph draws different conclusions about those. --SoledadKabocha (talk) 16:20, 17 February 2014 (UTC)