The Effect of Low Doses of Memantine on Serum Levels of Inflammatory Mediators in Methadone-Dependent Rats

Opioid abuse is a major and challenging public health problem with a broad range of physical, mental, and psychiatric consequences worldwide. This study was designed to evaluate the effect of low doses of memantine on serum levels of inflammatory mediators in methadone-dependent rats. This study was performed on 40 male wistar rats weighing 300-350 grams in four groups (n = 10). The rats were weighed at the beginning and the end of the study, and fasting blood glucose was measured by glucometer. Within 10 days, one group received intraperitoneal methadone 5 mg/kg, two groups received memantine 30 minutes before methadone injection subcutaneously 1 and 2 mg/kg, respectively, and the last group received normal saline. At the end, rats were sacrificed, and serum levels of high-sensitivity C-reactive protein (hsCRP), nuclear factor kappa B (NF-kB), tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), and lipid profiles were measured. Thera was a significant difference between the four groups in the mean level of NFκβ (P = 0.040) and hsCPR (P = 0.020). There was a significant difference between lipid profiles in mean levels of low-density lipoprotein (LDL) (P < 0.001), high-density lipoprotein (HDL) (P = 0.040), and triglyceride (P = 0.030). Our results showed that dependence on methadone affects the level of inflammatory mediators, and memantine could reduce these levels. Therefore, memantine can be considered as a new anti-addiction approach in the treatment of opioid-dependent patients who are on methadone maintenance treatment (MMT).