Anandamide induces cardiorespiratory reflexes via vasosensory nerves in the anaesthetized rat.

Smith, Paula J W; Smith, Paula; McQueen, Daniel S

Abstract

We tested the hypothesis that sensory nerves innervating blood vessels play a role in the local and systemic regulation of the cardiovascular and respiratory (CVR) systems. We measured CVR reflexes evoked by administration of anandamide (86 – 863 nmoles) and capsaicin (0.3 – 10 nmoles) into the hindlimb vasculature of anaesthetized rats.
Anandamide and capsaicin each caused a rapid dose-dependent reflex fall in blood pressure and an increase in ventilation when injected intra-arterially into the hindlimb.
Action of both agonists at the vanilloid receptor (VR1) on perivascular sensory nerves was investigated using capsazepine (1 mg kg-1 i.a.) a competitive VR1 antagonist, ruthenium red (1 mg kg-1 i.a.), a non-competitive antagonist at VR1, or a desensitizing dose of capsaicin (200 nmoles i.a.). The cannabinoid receptor antagonist SR141716 (1 mg kg-1 i.a.) was used to determine agonist activity at the CB1 receptor.
Capsazepine, ruthenium red, or acute VR1 desensitization by capsaicin-pretreatment, markedly attenuated the reflex CVR responses evoked by anandamide and capsaicin (P

• Journal Article Type: Article
• Publication Date: Oct 1, 2001
• Deposit Date: Jun 26, 2008
• Print ISSN: 0007-1188
• Electronic ISSN: 1476-5381
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 134
• Issue: 3
• Pages: 655-663
• DOI: https://doi.org/10.1038/sj.bjp.0704296
• Keywords: Anandamide; Capsaicin; Effects; Sensory nerves; Cardiovascular-respiratory reflexes; Vanilloid receptor; Rats
• Public URL: http://researchrepository.napier.ac.uk/id/eprint/1659
• Publisher URL: http://dx.doi.org/10.1038/sj.bjp.0704296