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A Novel in vivo Gene Transfer Technique and in vitro Cell Based Assays for the Study of Bone Loss in Musculoskeletal Disorders
Published on: June 8, 2014
Inhibition of nitric oxide synthase blocks osteoclastic bone resorption in adaptive bone modeling
R A Chole1, S P Tinling, E Leverentz
1Department of Otolaryngology, Washington University, St. Louis, MO 63110-1007, USA.
Acta Oto-Laryngologica
|December 5, 1998
Summary
Nitric oxide (NO) mediates adaptive bone remodeling in gerbil auditory bullae. Inhibiting nitric oxide synthase (NOS) with L-NAME reduced osteoclast activity during pressurized bone modeling.
Area of Science:
- Bone biology
- Physiology
- Pharmacology
Background:
- Bone remodeling is a continuous process involving osteoblasts and osteoclasts.
- Adaptive bone modeling responds to mechanical stimuli.
- The role of nitric oxide (NO) in bone remodeling is not fully understood.
Purpose of the Study:
- To investigate the role of NO in adaptive bone modeling of the gerbil auditory bulla.
- To determine if nitric oxide synthase (NOS) inhibition affects bone modeling under pressure.
Main Methods:
- Gerbil auditory bullae were subjected to controlled pressurization.
- Systemic administration of L-N(G)-nitro-arginine-methyl ester (L-NAME), a NOS inhibitor, was used.
- Osteoclast surface (Oc.S/BS), mineral apposition rate (MAR), and bone formation rate (BFR) were quantified.
Main Results:
- Pressurization induced significant bone modeling with increased osteoclast surface.
- L-NAME treatment significantly reduced osteoclast surface in pressurized bullae.
- L-NAME suppressed bone surface (BSf) in unpressurized bullae but did not affect MAR or BFR in pressurized bullae.
Conclusions:
- Nitric oxide is likely a mediator of osteoclastic resorption during adaptive bone modeling.
- NOS isoforms play a role in regulating bone remodeling in response to mechanical stress.
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