Canan Kucuk, Nihal Kadiogullari

Evaluation of the effects of dexmedetomidine and midazolam on plasma and cerebrospinal fluid beta-endorphin levels in rats

Endorphins are endogenous peptides that play a role in the regulation of pain, behavior, neuroendocrine and autonomic functions. In our study, we aimed to investigate the role of β endorphins in these effects of midazolam and dexmedetomidine. In this experimental study, 36 rats were divided into 6 groups. Group 1: (control) (n=6): An average of 100-150μl CSF samples were obtained after general anesthesia was achieved. An intracardiac 3-4ml blood sample was then taken. Group 2: (sham) (n=6): intraperitoneal 1 mL saline was administered. For all other groups after general anesthesia; Group 3: (midazolam-1) (n=6): intraperitoneal 4mg/kg midazolam was administered. Group 4: (midazolam-2) (n=6): 12mg/kg midazolam was administered intraperitoneally. Group 5: (Dexmedetomidine-1) (n=6): Dexmedetomidine 50μg/kg was administered intraperitoneally. Group 6: (Dexmedetomidine-2) (n=6): Dexmedetomidine 150 μg/kg was administered intraperitoneally.CSF and plasma samples were taken with the same method. All samples were stored at -80 °C. No statistically significant difference was found between the levels of rat CSF β-endorphin. However, when the plasma ß-endorphin levels of rats were evaluated, there was a statistically significant difference between the groups. No difference was found between the levels of plasma ß-endorphin in the patients who received midazolam, while plasma ß-endorphin levels of 50 μg/kg with dexmedetomidine were found to be lower than the control group. However, the values of the 150 μg/kg dexmedetomidine group did not support this result. Different findings from both this study and in vitro and human studies; the number of subjects, the use of different drug doses, the differences in measurement times, the absence of control groups may be due to methodological differences, and more research is needed.

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