Dexmedetomidine acts as an oxidative damage prophylactic in rats exposed to ionizing radiation.
OBJECTIVE
To investigate the effects of dexmedetomidine on oxidative injury caused by ionizing radiation.


METHODS
Randomized controlled experimental study.


METHODS
Department of radiation oncology and research laboratory of an academic hospital.


METHODS
Twenty-eight rats were randomized to 4 groups (n=7 per group). Group S rats were administered physiologic serum; group SR rats were administered physiologic serum and 10 Gy external ionizing radiation. Groups D100 and D200 were administered 100 and 200 μg/kg dexmedetomidine intraperitoneally, respectively, 45 minutes before ionizing radiation.


METHODS
Liver, kidney, lung, and thyroid tissue and serum levels of antioxidant enzymes (glutathione peroxidase [GPX], superoxide dismutase, and catalase) and oxidative metabolites (advanced oxidation protein products, malondialdehyde, and nitrate/nitrite, and serum ischemia-modified albumin) were measured 6 hours postprocedure.


RESULTS
In group SR, IR decreased antioxidant enzyme levels and increased oxidative metabolite levels (P<.05). In plasma, antioxidant enzyme levels were higher and oxidative metabolite levels were lower in groups D100 and D200 than in group SR (P<.01). In tissues, hepatic and lung GPX levels were higher in groups D100 and D200 than in group SR (P<.001). Renal and thyroid GPX levels were higher in D200 than in group SR (P<.01). Thyroid superoxide dismutase levels were higher in groups D100 and D200 than in group SR (P<.01). Renal, lung, and thyroid catalase levels were higher in group D200 than in group SR (P<.01). Hepatic, renal, and lung advanced oxidation protein products and malondialdehyde levels were lower in groups D100 and D200 than in group SR (P<.01). Hepatic, renal, and lung nitrate/nitrite levels were lower in group D200 than in group SR (P<.05).


CONCLUSIONS
Dexmedetomidine preserves the antioxidant enzyme levels and reduces toxic oxidant metabolites. Therefore, it can provide protection from oxidative injury caused by ionizing radiation.
Karadeniz Technical University, Medical Faculty, Department of Anaesthesiology and Intensive Care, Trabzon, Turkey. Electronic address: dilekkutanis@gmail.com.
Dilek
D
Kutanis
Karadeniz Technical University, Medical Faculty, Department of Anaesthesiology and Intensive Care, Trabzon, Turkey.
Engin
E
Erturk
Karadeniz Technical University, Medical Faculty, Department of Anaesthesiology and Intensive Care, Trabzon, Turkey.
Ahmet
A
Besir
Giresun University, Medical Faculty, Department of Anaesthesiology and Intensive Care, Giresun, Turkey.
Yucel
Y
Demirci
Hitit University, Corum Education and Research Hospital, Corum, Turkey.
Selcuk
S
Kayir
Karadeniz Technical University, Medical Faculty, Department of Anaesthesiology and Intensive Care, Trabzon, Turkey.
Ali
A
Akdogan
Karadeniz Technical University, Medical Faculty, Department of Biochemistry, Trabzon, Turkey.
Birgul
B
Vanizor Kural
Karadeniz Technical University, Medical Faculty, Department of Radiation Oncology, Trabzon, Turkey.
Zumrut
Z
Bahat
Karadeniz Technical University, Medical Faculty, Department of Radiation Oncology, Trabzon, Turkey.
Emine
E
Canyilmaz
Karadeniz Technical University, Medical Faculty, Department of Biochemistry, Trabzon, Turkey.
Hanife
H
Kara
D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage / Q000494:pharmacology*; D015415:Biomarkers / Q000032:analysis / Q000097:blood; D002374:Catalase / Q000032:analysis / Q000378:metabolism; D020927:Dexmedetomidine / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D007274:Injections, Intraperitoneal; D007668:Kidney / Q000201:enzymology; D008099:Liver / Q000201:enzymology; D008168:Lung / Q000201:enzymology; D008297:Male; D008315:Malondialdehyde / Q000032:analysis; D018384:Oxidative Stress / Q000187:drug effects*; D010088:Oxidoreductases / Q000032:analysis / Q000378:metabolism*; D011446:Prospective Studies; D011833:Radiation Injuries, Experimental / Q000097:blood / Q000517:prevention & control*; D011839:Radiation, Ionizing; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012709:Serum Albumin; D000075462:Serum Albumin, Human; D013482:Superoxide Dismutase / Q000032:analysis / Q000378:metabolism; D013961:Thyroid Gland / Q000201:enzymology
D018712:Analgesics, Non-Narcotic; D000975:Antioxidants; D015415:Biomarkers; D012709:Serum Albumin; C561522:ischemia-modified albumin; D008315:Malondialdehyde; D020927:Dexmedetomidine; D010088:Oxidoreductases; D002374:Catalase; D013482:Superoxide Dismutase; D000075462:Serum Albumin, Human
Dexmedetomidine; Ionizing radiation; Oxidative damage