Ss. Barros et Ej. Gimeno, Cell differentiation and bone protein synthesis in the lungs of sheep withspontaneous calcinosis, J COMP PATH, 123(4), 2000, pp. 270-277
Citations number
32
Categorie Soggetti
Veterinary Medicine/Animal Health","Medical Research Diagnosis & Treatment
The lungs of three sheep with spontaneous enzootic calcinosis induced by th
e calcinogenic plant Nierembergia veitchii (Nv) were examined electron micr
oscopically and immunohistochemically. The main ultrastructural changes wer
e activation of fibroblasts and modified smooth muscle cells (SMCs) in the
pulmonary interstitium, with an increase in extracellular matrix and precip
itation of calcium, either in a laminated pattern or as amorphous aggregate
s. Macrophages and multinucleated giant cells, some with calcium crystals i
n the cytoplasm, were found in areas of increased extracellular matrix. Thi
ckening and replication of the basal lamina of capillaries were prominent.
The hone proteins osteocalcin? osteopontin and osteonectin were detected im
munohistochemically in the cytoplasm of activated fibroblasts, in modified
SMCs and in the extracellular matrix. It is suggested that 1,25-dihydroxyvi
tamin D-3 in Nv induces cellular differentiation and the synthesis of a cal
cifiable matrix. (C) 2000 Harcourt Publishers Ltd.