Bone resorption and circulating PTH-like bioactivity in an animal model of hypercalcaemia of malignancy.
An in vivo model of humoral hypercalcaemia of malignancy has been used to examine the role of circulating PTH-like bioactivity in the development of bone resorption and hypercalcaemia. After inoculation of cells from a renal carcinoma cell line into nude mice, circulating PTH-like bioactivity as measured by the sensitive renal and metatarsal cytochemical bioassays for PTH was elevated in only 18% and 53% of the mice respectively. Bone resorption was elevated in all the mice investigated irrespective of the level of PTH-like bioactivity. Thus, in this model, while the circulating PTH-like moiety is more potent when acting on bone, it did not correlate with the degree of bone resorption suggesting that it may not be the sole cause of the hypercalcaemia.
Mehdizadeh
S
S
Dept of Chemical Pathology, Charing Cross Hospital, London, UK.
Alaghband-Zadeh
J
J
Gusterson
B
B
Arlot
M
M
Bradbeer
J N
JN
Loveridge
N
N
D000818:Animals; D001862:Bone Resorption; D001842:Bone and Bones / Q000473:pathology; D002292:Carcinoma, Renal Cell / Q000473:pathology / Q000503:physiopathology*; D002460:Cell Line; D005260:Female; D006801:Humans; D006934:Hypercalcemia / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D007680:Kidney Neoplasms / Q000473:pathology / Q000503:physiopathology*; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D010281:Parathyroid Hormone / Q000097:blood*; D014183:Transplantation, Heterologous
D010281:Parathyroid Hormone