Inhibition of bone resorption by NDGA. Cultures of mature osteoclast-like MNCs obtained from rat whole bone marrow cultures were replated on dentine slices (a, b) or osteologic slides (c–e) and cultured for 48 h in the presence of the indicated concentrations of NDGA. The image of pits (c), total areas of resorption pits (a, d), and the total number of resorption pits (b, e) were obtained as described in Materials and Methods. Data represent means±s.d. (n=4). Data were analyzed by Student’s t-test. *P<0.05, **P<0.01, and ***P<0.001 compared with the culture without NDGA.