Augmentation of analgesic effects following co-administration of vanilloid receptor blocker and cyclooxygenase type 2 inhibitor in rat formalin test
|
Parisa Karimi Dehkordi , Zahra Mousavi , Nima Naderi * |
Department of Toxicology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran |
|
Abstract: (1978 Views) |
Background and aims: The transient receptor potential cation channel subfamily V member 1 (TRPV1) receptors play a substantial role in pain transmission and the receptor antagonist capsazepine could alleviate pain in various pharmacological models. On the other hand, the enzyme cyclooxygenase type 2 (COX-2) has been shown to exist in central nervous system, particularly in hippocampal glutamatergic neurons as well as in cortex and the enzyme inhibition could alleviate pain transmission and perception. The aim of the present study was to investigate the analgesic effect of capsazepine and its possible interaction with COX-2 inhibition in the brain.
Methods: Male wistar rats (200–250 g) were used in this study. One week after insertion of a stainless steel guide cannula by stereotaxic surgery, drugs were administered into left lateral ventricle on the day of experiment 10 min before formalin test and the pain related behavior of the rat was measured based on method described by Dubuisson and Dennis. Experimental groups consisted of capsazepine (5 and 50 nM), celecoxib (2 and 20 nM), and co-administration of capsazepine (5 nM) and celecoxib (2 nM).
Results: Results showed a significant decrease in pain related behavior in rats received capsazepine 5 nM (92.4 ± 1.1), capsazepine 50 nM (57.0 ± 2.1), celecoxib 2 nM (83.9 ± 1.1), or celecoxib 20 nM (51.6 ± 1.4) compared with the control (103.60 ± 2.0) group. Moreover, co-administration of celecoxib (2 nM) and capsazepine (5 nM) significantly decreased pain related behavior of rats (50.6 ± 0.8) compared with the group received celecoxib (2 nM) or capsazepine (5 nM) alone, respectively.
Conclusion: The results suggest a possible additive and/or synergistic interaction between celecoxib and capsazepine in analgesic effects in formalin test.
|
|
Keywords: Formalin test, pain, Cyclooxygenase type 2, Capsazepine, TRPV1 |
|
Full-Text [PDF 986 kb]
(697 Downloads)
|
Type of Study: Original Research |
Subject:
Neuroscience
|
|
|
|
|
Add your comments about this article |
|
|