|
|
||||||||
1 Oral and Maxillofacial Surgery, Eastman Dental Institute, London WC1X 8LD; and 2 Department of Anatomy and Developmental Biology, University College London, London WC1E 6BT, United Kingdom
We examined the effects of
HCO3
and CO2 acidosis on
osteoclast-mediated Ca2+ release from 3-day cultures of
neonatal mouse calvaria. Ca2+ release was minimal above pH
7.2 in control cultures but was stimulated strongly by the addition of
small amounts of H+ to culture medium
(HCO3
acidosis). For example, addition of 4 meq/l
H+ reduced pH from 7.12 to 7.03 and increased
Ca2+ release 3.8-fold. The largest stimulatory effects (8- to 11-fold), observed with 15-16 meq/l added H+, were
comparable to the maximal Ca2+ release elicited by
1,25-dihydroxyvitamin D3
[1,25(OH)2D3; 10 nM], parathyroid hormone (10 nM), or prostaglandin E2 (1 µM); the action of these
osteolytic agents was attenuated strongly when ambient pH was increased
from ~7.1 to ~7.3. CO2 acidosis was a less effective
stimulator of Ca2+ release than HCO3
acidosis over a similar pH range. Ca2+ release stimulated
by HCO3
acidosis was almost completely blocked by
salmon calcitonin (20 ng/ml), implying osteoclast involvement. In whole
mount preparations of control half-calvaria, ~400 inactive
osteoclast-like multinucleate cells were present; in calvaria exposed
to HCO3
acidosis and to the other osteolytic agents
studied, extensive osteoclastic resorption, with perforation of bones,
was visible. HCO3
acidosis, however, reduced numbers
of osteoclast-like cells by ~50%, whereas
1,25(OH)2D3 treatment caused increases of
~75%. The results suggest that HCO3
acidosis
stimulates resorption by activating mature osteoclasts already present
in calvarial bones, rather than by inducing formation of new
osteoclasts, and provide further support for the critical role of
acid-base balance in controlling osteoclast function.
calcium release; carbon dioxide; bicarbonate ion; acid-base balance; osteolysis
This article has been cited by other articles:
![]() |
T. R Fenton, M. Eliasziw, A. W Lyon, S. C Tough, and D. A Hanley Meta-analysis of the quantity of calcium excretion associated with the net acid excretion of the modern diet under the acid-ash diet hypothesis Am. J. Clinical Nutrition, October 1, 2008; 88(4): 1159 - 1166. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. M Macdonald, A. J Black, L. Aucott, G. Duthie, S. Duthie, R. Sandison, A. C Hardcastle, S. A Lanham New, W. D Fraser, and D. M Reid Effect of potassium citrate supplementation or increased fruit and vegetable intake on bone metabolism in healthy postmenopausal women: a randomized controlled trial Am. J. Clinical Nutrition, August 1, 2008; 88(2): 465 - 474. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. A. Lanham-New The Balance of Bone Health: Tipping the Scales in Favor of Potassium-Rich, Bicarbonate-Rich Foods J. Nutr., January 1, 2008; 138(1): 172S - 177S. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. A Welch, S. A Bingham, J. Reeve, and K. Khaw More acidic dietary acid-base load is associated with reduced calcaneal broadband ultrasound attenuation in women but not in men: results from the EPIC-Norfolk cohort study Am. J. Clinical Nutrition, April 1, 2007; 85(4): 1134 - 1141. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Ito, S. Haito, M. Furumoto, Y. Uehata, A. Sakurai, H. Segawa, S. Tatsumi, M. Kuwahata, and K.-i. Miyamoto Unique uptake and efflux systems of inorganic phosphate in osteoclast-like cells Am J Physiol Cell Physiol, January 1, 2007; 292(1): C526 - C534. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. McCarthy The Physiology of Bone Blood Flow: A Review J. Bone Joint Surg. Am., November 1, 2006; 88(suppl_3): 4 - 9. [Abstract] [Full Text] [PDF] |
||||
![]() |
A Del Fattore, B Peruzzi, N Rucci, I Recchia, A Cappariello, M Longo, D Fortunati, P Ballanti, M Iacobini, M Luciani, et al. Clinical, genetic, and cellular analysis of 49 osteopetrotic patients: implications for diagnosis and treatment J. Med. Genet., April 1, 2006; 43(4): 315 - 325. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. M Macdonald, S. A New, W. D Fraser, M. K Campbell, and D. M Reid Low dietary potassium intakes and high dietary estimates of net endogenous acid production are associated with low bone mineral density in premenopausal women and increased markers of bone resorption in postmenopausal women Am. J. Clinical Nutrition, April 1, 2005; 81(4): 923 - 933. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Ito, N. Matsuka, M. Izuka, S. Haito, Y. Sakai, R. Nakamura, H. Segawa, M. Kuwahata, H. Yamamoto, W. J. Pike, et al. Characterization of inorganic phosphate transport in osteoclast-like cells Am J Physiol Cell Physiol, April 1, 2005; 288(4): C921 - C931. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. A New, H. M MacDonald, M. K Campbell, J. C Martin, M. J Garton, S. P Robins, and D. M Reid Lower estimates of net endogenous noncarbonic acid production are positively associated with indexes of bone health in premenopausal and perimenopausal women Am. J. Clinical Nutrition, January 1, 2004; 79(1): 131 - 138. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Li, W.-S. Hou, C. R. Escalante-Torres, B. D. Gelb, and D. Bromme Collagenase Activity of Cathepsin K Depends on Complex Formation with Chondroitin Sulfate J. Biol. Chem., August 2, 2002; 277(32): 28669 - 28676. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. HOEBERTZ, S. MEGHJI, G. BURNSTOCK, and T. R. ARNETT Extracellular ADP is a powerful osteolytic agent: evidence for signaling through the P2Y1 receptor on bone cells FASEB J, May 1, 2001; 15(7): 1139 - 1148. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |