Skin-pop (SP) of PTHrP1-86 to mouse models of osteoporosis can not only activate 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) and promote bone formation but also save lives of the mice that have both PTH and 1α(OH)ase knocked out and regulate receptor activator of nuclear factor kappa B ligand and osteoprotegerin expression, which is to restrain bone resorption, and further prove the bone formation enhancement of exogenous PTHrP [15]. This evidence concerns the gene PTHLH and osteoporosis.