Potentiating Effect of Methylmorphine on Flunitrazepam-induced Cholesterogenesis in Brain: A rat Model


  • Esther Abam Biochemistry Unit, Chemical and Food Sciences, Bells University of Technology, Ota Author


Methylmorphine, flunitrazepam, ATPases, hyperbilirubinemia, hypercholesterolemia, cholesterogenesis


Methylmorphine (codeine) and flunitrazepam (rohypnol) are central nervous system depressants and common drugs of abuse among youths, despite the restriction in production and distribution placed on these drugs in Nigeria. The aim of this study is to assess the toxic effects of combined abuse of these drugs. Thirty-five (35) male Wistar rats were divided into five (5) groups of seven animals each. Group 1 served as control and was administered distilled water only, groups 2 and 3 received a daily dose of 3.25mg kg-1 bw of codeine and 0.03mg kg-1 bw rohypnol respectively. Groups 4 and 5 both received combined doses of 3.25mg kg-1 bw of codeine and 0.03mg kg-1 bw of codeine and 0.03mg kg-1bw of rohypnol daily. All groups were exposed for 28days except group 5 which was sacrificed after one week of withdrawal of treatments (day 35). At the end of the exposure, some liver and brain function biomarkers were studied spectrophotometrically. Exposure to either codeine or rohypnol resulted in significantly reduced (p<0.05) plasma creatinine levels, and reduced activities of Ca2+-Mg2+- and total ATPases in the brain. Hyperbilirubinemia, hypercholesterolemia, elevated plasma and liver transaminases and a 5-fold increase in brain cholesterol were observed as a result of combined exposure to both toxicants. Interaction between codeine and rohypnol was mostly additive and synergistic in the biomarkers studied with a potentiating effect of codeine on rohypnol with regards to brain cholesterol. The enhanced psychoactivity produced in co-abuse of both drugs may be mediated by enhanced cholesterogenesis in the brain.


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How to Cite

Potentiating Effect of Methylmorphine on Flunitrazepam-induced Cholesterogenesis in Brain: A rat Model. (2022). Nigerian Journal of Biochemistry and Molecular Biology, 37(2), 111-121. https://www.nsbmb.org.ng/journals/index.php/njbmb/article/view/10