MrgC receptor activation reverses chronic morphine-evoked alterations of glutamate transporters and nNOS in rats / 生理学报
Acta Physiologica Sinica
;
(6): 449-456, 2014.
Article
in Chinese
| WPRIM
| ID: wpr-297472
ABSTRACT
This study was aimed to investigate the mechanisms underlying the modulation effect of Mas-related gene (Mrg) C receptors (MrgC) on morphine tolerance. Saline, morphine (20 μg), morphine plus bovine adrenal medulla 8-22 (BAM8-22, 1 nmol) or (Tyr(6))-2-MSH-6-12 (MSH, 5 nmol) were administered intrathecally in rats for 6 days. Pain-related molecules in the spinal cord and dorsal root ganglion (DRG) were examined using Western blot, immunocytochemistry and RT-PCR techniques. The results showed that intrathecal administration of the selective MrgC receptor agonists (BAM8-22 or MSH) remarkably attenuated or abolished chronic morphine-evoked reduction in glutamate transporters (GLAST, GLT-1 and EAAC1) in the spinal cord and increase in neuronal nitric oxide synthase (nNOS) in the spinal cord as well as DRG. In addition, MrgC receptor-like immunoreactivity (IR) was detected in superficial laminae of the spinal cord. Chronic morphine induced significant increases in MrgC receptor-IR in the spinal cord and MrgC receptor mRNA levels in DRG. These results suggest that the modulation of pro-nociceptive mediators in the spinal cord and DRG underlies the inhibition of morphine tolerance by MrgC receptor activation.
Full text:
Available
Index:
WPRIM (Western Pacific)
Main subject:
Pain
/
Peptide Fragments
/
Pharmacology
/
Spinal Cord
/
Pain Measurement
/
Rats, Sprague-Dawley
/
Amino Acid Transport System X-AG
/
Receptors, G-Protein-Coupled
/
Drug Tolerance
/
Nitric Oxide Synthase Type I
Limits:
Animals
Language:
Chinese
Journal:
Acta Physiologica Sinica
Year:
2014
Type:
Article
Similar
MEDLINE
...
LILACS
LIS