Parathyroid hormone immunoreactivity in the plasma filtrate of uremic patients

Plasma filtrate of uremic patients concentrated and fractionated by gel filtration consisted of a large peak with C-terminal immunoreactivity and a small peak with N-terminal immunoreactivity. Further analysis of the first peak with C-terminal immunoreactivity by ion exchange chromatography revealed at least 3 peaks indicating the presence of three peaks with a similar immunological behavior but different charge. The elution profile in a patient under chronic hemofiltration was different in pattern compared with that in 2 patients under conventional hemodialysis.