Abstract |
The pain modulatory role of the paragigantocellularis lateralis nucleus (LPGi) and the 17β-estradiol has thoroughly been probed. This study investigates the contribution of ionotropic glutamate receptors in pain modulatory effect of intra-LPGi injection of 17β-estradiol. For this purpose, the LPGi nucleus cannulation was performed and drugs were injected into this nucleus, 15 min prior to the formalin test. The duration of formalin-induced flexing and licking behaviors was recorded for 60 min immediately after formalin injection. The results showed that the flexing behavior is significantly decreased by intra-LPGi injection of 0.8 µmol 17β-estradiol duringboth phases of formalin test (P < 0.001). However, 17β-estradiol attenuated the licking duration only in the second phase (P < 0.001). Interestingly, NMDA and AMPA/ kainate receptor antagonists (AP5 and CNQX, respectively) significantly counteracted the analgesic effect of intra-LPGi injection of 17β-estradiol in both phases of the formalin test (P < 0.001). Consequently, the revealing results showed that the analgesic effect of intra-LPGi injection of 17β-estradiol on acute inflammatory pain might be mediated via the activation of ionotropic glutamate receptors.
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Authors | Roghaieh Khakpay, Maryam Azaddar, Fatemeh Khakpai |
Journal | Acta neurologica Belgica
(Acta Neurol Belg)
Vol. 120
Issue 3
Pg. 653-660
(Jun 2020)
ISSN: 2240-2993 [Electronic] Italy |
PMID | 30132138
(Publication Type: Journal Article)
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Chemical References |
- Irritants
- Receptors, AMPA
- Receptors, N-Methyl-D-Aspartate
- Formaldehyde
- Estradiol
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Topics |
- Animals
- Estradiol
(metabolism, pharmacology)
- Formaldehyde
(toxicity)
- Irritants
(toxicity)
- Male
- Medulla Oblongata
(drug effects, metabolism)
- Pain
(chemically induced, metabolism)
- Pain Measurement
- Rats
- Rats, Wistar
- Receptors, AMPA
(metabolism)
- Receptors, N-Methyl-D-Aspartate
(metabolism)
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