Journal
NEUROSCIENCE LETTERS
Volume 344, Issue 1, Pages 21-24Publisher
ELSEVIER SCI IRELAND LTD
DOI: 10.1016/S0304-3940(03)00405-1
Keywords
arthritis; blood flow; capsaicin; knee joint; Mu opioid receptor; neurogenic inflammation; neuropeptides; opioids
Categories
Ask authors/readers for more resources
In joints, synthetic mu-opioids reduce inflammatory changes such as protein extravasation and associated oedema formation. However, the effect of endogenous opioid peptides on other inflammatory processes such as altered tissue blood flow has not been investigated. The present study examined the peripheral effects of the endogenous mu-opioid ligand endomorphin-1 (EM-1) on rat knee joint blood flow using laser Doppler perfusion imaging. Topical application of EM-1 (10(-16)-10(-9) mol) to exposed rat knee joints resulted in a dose-dependent increase in synovial vascular resistance with a maximum rise of 56% occurring with the 10(-9) mol dose. Destruction of unmyelinated articular afferents by capsaicin treatment completely abolished the hypoaemic effects of EM-1. These findings suggest that EM-1 acts peripherally in knee joints to decrease synovial blood flow, and this hypoaemic response is dependent on the presence of capsaicin-sensitive nerves. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available