Volume 20, Number 7 (10-2017)                   amuj 2017, 20(7): 23-33 | Back to browse issues page


XML Persian Abstract Print


Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Khakpay R, Feyzi H, Sheikhzadeh Hesari F. The Role of NMDA Receptors of the Paragigantocellularis Lateralis Nucleus in the Antinociceptive Effect of 17β-estradiol in Ovariectomized Female Rats . amuj. 2017; 20 (7) :23-33
URL: http://amuj.arakmu.ac.ir/article-1-5230-en.html

Assistant Professor of Physiology, Department of Animal Sciences, Faculty of Natural Sciences, University of Tabriz, Tabriz, Iran , rkhakpai@gmail.com
Abstract:   (62 Views)
Abstract
Background: 17β-Estradiol modulates nociception by binding to the estrogen receptors and also by allosteric interaction with other membrane-bound receptors like the NMDA receptors. The paragigantocellularis lateralis nucleus (LPGi) is also involved in the pain modulation. In this study, the role of NMDA receptors of the LPGi nucleus has been investigated in the 17β-estradiol-induced pain modulation in the ovariectomized rats.
Materials and Methods: In this study, the female Wistar rats in the range of 200-270 gr were used. In order to study the role of the NMDA receptors in the 17β-estradiol-induced pain modulation in the ovariectomized rats, primarily, rats were bilaterally ovariectomized and immediately cannulation of the LPGi nucleus was performed. Then, drugs were injected and 15 minutes later 50 μl of 5% formalin was injected into the rat's hind paw; and formalin-induced paw jerking behaviour was recorded for 60 min.
Results: The results of the present study showed that the intra-LPGi injection of 17β-estradiol significantly reduced the paw jerking behavior both in the first and in the second phases of formalin test. Pretreatment of the LPGi nucleus by NMDA receptor antagonist (AP5) neutralized the antinociceptive effect of 17β-estradiol on the paw jerking frequency in the both phases of formalin test; and induced hyperalgesia in the both phases of this behavior.
Conclusion: These results indicated that the intra-LPGi injection of 17β-estradiol produces modest analgesia on the formalin-induced inflammatory pain. Therefore, it can be concluded that the NMDA receptors of the paragigantocellularis lateralis nucleus are probably involved in the antinociceptive effect of 17β-estradiol in the ovariectomized rats.

 
Full-Text [PDF 865 kb]   (33 Downloads)    
Type of Study: Original Atricle | Subject: Basic Sciences
Received: 2017/07/17 | Accepted: 2017/09/3 | Published: 2017/09/12

Add your comments about this article : Your username or email:
Write the security code in the box

Send email to the article author


© 2015 All Rights Reserved | Arak Medical University Journal

Designed & Developed by : Yektaweb