Affordable Access

deepdyve-link
Publisher Website

Is nitric oxide a mediator of the effects of low-intensity electrical stimulation on bone in ovariectomized rats?

Authors
  • Lirani-Galvão, A P R
  • Lazaretti-Castro, M
  • Portero-Muzy, N
  • Bergamaschi, C T
  • Silva, O L
  • Carvalho, A B
  • Delmas, P D
  • Chavassieux, P
Type
Published Article
Journal
Calcified Tissue International
Publisher
Springer-Verlag
Publication Date
Jul 01, 2010
Volume
87
Issue
1
Pages
52–59
Identifiers
DOI: 10.1007/s00223-010-9357-0
PMID: 20383765
Source
Medline
License
Unknown

Abstract

Low-intensity electrical stimulation (LIES) may counteract the effects of ovariectomy (OVX) on nitric oxide synthase (NOS) expression, osteocyte viability, bone structure, and microarchitecture in rats (Lirani-Galvão et al., Calcif Tissue Int 84:502-509, 2009). The aim of the present study was to investigate if these effects of LIES could be mediated by NO. We analyzed the effects of NO blockage (by L-NAME) in the response to LIES on osteocyte viability, bone structure, and microarchitecture in OVX rats. Sixty rats (200-220 g) were divided into six groups: sham, sham-L-NAME (6 mg/kg/day), OVX, OVX-L-NAME, OVX-LIES, and OVX-LIES-L-NAME. After 12 weeks, rats were killed and tibiae collected for histomorphometric analysis and immunohistochemical detection of endothelial NOS (eNOS), inducible NOS (iNOS), and osteocyte apoptosis (caspase-3 and TUNEL). In the presence of L-NAME, LIES did not counteract the OVX-induced effects on bone volume and trabecular number (as on OVX-LIES). L-NAME blocked the stimulatory effects of LIES on iNOS and eNOS expression of OVX rats. Both L-NAME and LIES decreased osteocyte apoptosis. Our results showed that in OVX rats L-NAME partially blocks the effects of LIES on bone structure, turnover, and expression of iNOS and eNOS, suggesting that NO may be a mediator of some positive effects of LIES on bone.

Report this publication

Statistics

Seen <100 times