Association of morphine-induced analgesic tolerance with changes in gene expression of GluN1 and MOR1 in rat spinal cord and midbrain

Ahmadi, Shamseddin and Miraki, Fatemeh and Rostamzadeh, Jalal (2016) Association of morphine-induced analgesic tolerance with changes in gene expression of GluN1 and MOR1 in rat spinal cord and midbrain. Iranian Journal of Basic Medical Sciences, 19 (9). pp. 924-931.

[img]
Preview
Text
IJBMS_Volume 19_Issue 9_Pages 924-931.pdf

Download (1MB) | Preview
Official URL: http://ijbms.mums.ac.ir/article_7591.html

Abstract

Objective(s): We aimed to examine association of gene expression of MOR1 and GluN1 at mRNA level in the lumbosacral cord and midbrain with morphine tolerance in male Wistar rats. Materials and Methods: Analgesic effects of morphine administrated intraperitoneally at doses of 0.1, 1, 5 and 10 mg/kg were examined using a hot plate test in rats with and without a history of 15 days morphine (10 mg/kg) treatment. Morphine-induced analgesic tolerance was also assessed on days 1, 5, 10 and 15 of chronic morphine injections. Two groups with history of 15 days injections of saline or morphine (10 mg/kg) were decapitated on day 15 and their lumbosacral cord and midbrain were dissected for evaluating MOR1 and GluN1 gene expression. Results: The results of the hot plate test showed that morphine (5 and 10 mg/kg) induced significant analgesia in naïve rats but its analgesic effects in rats receiving 15 days injections of morphine (10 mg/kg) was decreased, indicating tolerance to morphine analgesia. The results also showed that the GluN1 gene expression in tolerant rats was decreased by 71 in the lumbosacral cord but increased by 110 in the midbrain compared to the control group. However, no significant change was observed for the MOR1 gene expression in both areas. Conclusion: It can be concluded that tolerance following administration of morphine (10 mg/kg) for 15 days is associated with site specific changes in the GluN1 gene expression in the spinal cord and midbrain but the MOR1 gene expression is not affected.

Item Type: Article
Subjects: QV pharmacology
Divisions: Journals > Iranian J Basic Medical Sciences
Depositing User: ijbms ijbms
Date Deposited: 27 Sep 2017 16:48
Last Modified: 27 Sep 2017 16:48
URI: http://eprints.mums.ac.ir/id/eprint/5547

Actions (login required)

View Item View Item