Jg. Parthemore et al., ASSOCIATIONS AND DISSOCIATIONS BETWEEN SERUM BONE GLA PROTEIN AND ALKALINE-PHOSPHATASE IN SKELETAL METABOLISM, Journal of orthopaedic research, 11(5), 1993, pp. 671-676
Serum bone Gla protein (BGP) and alkaline phosphatase (AP) activity we
re compared for the assessment of skeletal status in 11 normal pregnan
t women, 12 normal women on days 3 and 13 of the menstrual cycle, five
postmenopausal women before and after 1 month of treatment with ethin
yl estradiol (20 mu g/day), five patients with cancer and hypercalcemi
a during treatment with calcitonin, and one patient with Paget disease
during treatment with Plicamycin. BGP and AP correlated with each oth
er only in the pregnant women. In all other circumstances, there was n
o correlation between these two serum osteoblast products. Furthermore
, there were conditions in which the two measurements became discordan
t. These studies demonstrate that BGP and AP commonly are dissociated
when used as measurements of skeletal status. Although both are osteob
last products, BGP and AP probably reflect different aspects of osteob
last differentiation and function.