FGF23 and secondary hyperparathyroidism: While some features of the adenine model are not representative of CKD (e.g. polyuria, weight loss), it does nonetheless recapitulate many of the features of advanced human CKD-MBD (depending on the dose and duration of administration): hyperphosphataemia, secondary hyperparathyroidism, FGF23 excess, calcitriol deficiency, high turnover osteodystrophy and ectopic calcification.