,28 In adenine-induced CKD in mice and in rats with progressive CKD due to polycystic kidney disease, high PTH is associated with cortical porosity development,9,11,12,29,30 Interestingly, the PTH response to CKD also differs due to the genetic strain of mice and these changes correlate with porosity development. This evidence concerns the gene PTH and polycystic kidney disease.