1. The plasma concentration of the α2HS-glycoprotein has been measured in 58 normal adults and in patients with Paget's disease of bone before (24) and during treatment (16).
2. The average plasma α2HS-glycoprotein was lower in the patients with Paget's disease than in the normal adults and was inversely related to plasma alkaline phosphatase activity (r = −0.55, n = 24, P<0.001).
3. When the patients with Paget's disease were treated with either diphosphonate or calcitonin, the plasma α2HS-glycoprotein concentration increased towards normal. In those patients treated with calcitonin, this increase was too rapid to be entirely accounted for by a cessation of bone formation.