Anti-inflammatory effects of limb ischaemic preconditioning are mediated by sensory nerve activation in rats.
Naunyn Schmiedebergs Arch Pharmacol
; 383(2): 179-89, 2011 Feb.
Article
em En
| MEDLINE
| ID: mdl-21181115
ABSTRACT
We have shown that ischaemic preconditioning ameliorates both the local periosteal and the systemic leukocyte activation evoked by limb ischaemia-reperfusion. We hypothesized that the activation of chemosensitive afferent nerves by transient ischaemia contributes to the protective mechanisms of ischaemic preconditioning via a calcitonin gene-related peptide (CGRP)-dependent mechanism. In Sprague-Dawley rats, 60-min complete limb ischaemia was followed by 180 min of reperfusion. In further experiments, the CGRP analogue hCGRP (0.3 µg kg(-1)) or ischaemic preconditioning (2 × 10-min ischaemia/10-min reperfusion) was applied prior to the ischaemia-reperfusion insult. Ischaemic preconditioning was performed in three subgroups in which animals received the CGRP receptor antagonist CGRP(8-37) (30 µg kg(-1) h(-1)), the chemosensitive afferent nerve inactivator resiniferatoxin (3 × 15 µg kg(-1), sc), or vehicle. The effects of CGRP(8-37) and resiniferatoxin on ischaemia-reperfusion without ischaemic preconditioning were also evaluated. In the tibial periosteum of rats, intravital fluorescence microscopy and immunohistochemistry revealed significant attenuations of ischaemia-reperfusion-induced post-ischaemic leukocyte-endothelial interactions (rolling and adherence in the postcapillary venules) and tissue intracellular adhesion molecule expression following ischaemic preconditioning or hCGRP administration. Administration of CGRP(8-37) or pretreatment of animals with resiniferatoxin reversed the anti-inflammatory effects of limb ischaemic preconditioning, but failed to affect the microcirculatory consequences of ischaemia-reperfusion without ischaemic preconditioning. The results suggest that activation of the chemo- (capsaicin-) sensitive afferent nerves is involved in the mechanisms of microcirculatory anti-inflammatory protection provided by limb ischaemic preconditioning. Controlled activation of chemosensitive C-fibres or the CGRP receptors by the induction of ischaemic preconditioning or other means may furnish therapeutic benefit by ameliorating the periosteal microcirculatory consequences of tourniquet ischaemia.
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Base de dados:
MEDLINE
Assunto principal:
Células Receptoras Sensoriais
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Traumatismo por Reperfusão
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Receptores de Peptídeo Relacionado com o Gene de Calcitonina
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Precondicionamento Isquêmico
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Antagonistas do Receptor do Peptídeo Relacionado ao Gene de Calcitonina
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Membro Posterior
Limite:
Animals
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Humans
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Male
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article