Carbonic anhydrase isoenzymes in isolated rat peripheral monocytes, tissue macrophages, and osteoclasts

Carbonic anhydrase II is induced in HL‐60 cells by 1,25‐dihydroxyvitamin D3: A model for osteoclast gene regulation

“…The effect of these hormones on the regulation of the CA II gene can now be studied at the molecular level. Although HL-60 cells express CA II, this is not so in cultured rat peripheral monocytes, and most types of macrophages [8]. Considering the close developmental relationships between osteoclasts and monocytes and macrophages, as well as the sometimes aberrant nature of genetic programs of neoplastic cells, these results are not surprising.…”

“…The osteopetrosis in CA II deficiency syndrome is an osteoclast-specific defect as shown by two lines of evidence. CA II in bone is found only in osteoclasts in a variety of species [6][7][8][9][10], and variation in the activity of CA II caused by hormonal treatment (e.g. parathyroid hormone) in bone culture influences the degree of bone resorption [11].…”

1 alpha,25-dihydroxyvitamin D3 regulates the expression of carbonic anhydrase II in nonerythroid avian bone marrow cells.

“…1,25(OH)2D3 induces an increase in bone resorption in vivo (1, 7) and in organ cultures (8, 9) but has no effect on the resorptive activity of isolated osteoclasts (10, 11). The increase in bone resorption is believed to be mediated primarily by means of an effect upon the proliferation and/or differentiation of osteoclast precursors within the hematopoietic bone marrow (12-15), leading to an increase in the number of mature osteoclasts (7,9 (13,14,19,20) and increases the proportion ofthe cells that can resorb bone (14).Taken together, these results suggest that this steroid hormone may specifically induce the differentiation of myelomonocytic precursors toward the macrophage and/or osteoclast lineage.One of the genes that is expressed at high levels in the osteoclast (21-23), but not in peripheral monocytes or mature macrophages (24), is the gene encoding carbonic anhydrase II (CAII). CAII is an enzyme that reversibly generates bicarbonate and protons from carbon dioxide and water (25).…”

“…One of the genes that is expressed at high levels in the osteoclast (21)(22)(23), but not in peripheral monocytes or mature macrophages (24), is the gene encoding carbonic anhydrase II (CAII). CAII is an enzyme that reversibly generates bicarbonate and protons from carbon dioxide and water (25).…”

Localization of Carbonic Anhydrase in Living Osteoclasts with Bodipy 558/568-modified Acetazolamide, a Thiadiazole Carbonic Anhydrase Inhibitor

“…Carbonic anhydrase, the enzyme that catalyzes the reversible hydration of CO 2 to carbonic acid, has been identified in osteoclasts of chickens (Gay and Mueller 1974;Anderson et al 1982), rats (Väänänen and Parvinen 1983;Marie and Hott 1987;Sundquist et al 1987), mice (Jilka et al 1985), and humans (Väänänen 1984). Inhibition of bone resorption by acetazolamide and other inhibitors of carbonic anhydrase has been demonstrated in vivo (Waite et al 1970;Waite 1972;Conaway et al 1973;Kenny 1985;Brown et al 1990) and in vitro, in whole-bone explants (Minkin and Jennings 1972;Mahgoub and Stern 1974;Hall and Kenny 1985a,b,1986Raisz et al 1988) and isolated osteoclasts (Hunter et al 1991).…”