Ildan F, Polat S, Oner A, Isbir T, Göçer A I, Tap O, Kaya M, Karadayi A
Department of Neurosurgery, Cukurova University, School of Medicine, Balcali, Adana, Turkey.
Neurosurgery. 1995 Apr;36(4):797-805. doi: 10.1227/00006123-199504000-00022.
Endorphins have been implicated in the pathophysiology of spinal cord injury. The effect of naloxone on the sodium- and potassium-activated and magnesium-dependent adenosine-5'-triphosphatase (Na(+)-K+/Mg+2 ATPase, EC.3.6.1.3.) activity, lipid peroxidation, and early ultrastructural findings were studied in rats at the early stage of spinal cord injury, produced with an aneurysm clip on the T2-T7 segments. The rats were divided into four groups. The 10 rats in Group I, which had no injury and received no medication, were used for determining Na(+)-K+/Mg+2 ATPase activity, the extent of lipid peroxidation (by measuring the level of thiobarbituric acid-reactive substances as malondialdehyde), and normal ultrastructural findings. On the 15 rats in Group II, without spinal cord injury, only laminectomy was performed to determine the effect of surgery on the biochemical indices and findings. In the 15 rats in Group III, physiological saline was administered intraperitoneally in an amount equivalent to that of the naloxone administered immediately after spinal cord injury. In the 15 rats in Group IV, 0.5 mg of naloxone was administered intraperitoneally as a single dose immediately after injury and again 60 minutes after injury. The Na(+)-K+/Mg+2 ATPase activity was promptly reduced after spinal cord injury and remained in a lower level than the levels of Groups I and II during 120 minutes after injury. Naloxone treatment, immediately after trauma, attenuated the inactivation of Na(+)-K+/Mg+2 ATPase. On the other hand, there was a significant difference in the malondialdehyde content between animals in Groups I and III. Naloxone treatment reduced the malondialdehyde content in Group IV.(ABSTRACT TRUNCATED AT 250 WORDS)
内啡肽与脊髓损伤的病理生理学有关。在通过用动脉瘤夹夹闭T2 - T7节段造成脊髓损伤的大鼠早期，研究了纳洛酮对钠钾激活的镁依赖性腺苷 - 5'-三磷酸酶（Na(+)-K+/Mg+2 ATPase，EC.3.6.1.3.）活性、脂质过氧化和早期超微结构改变的影响。大鼠被分为四组。第一组10只大鼠未受伤且未接受药物治疗，用于测定Na(+)-K+/Mg+2 ATPase活性、脂质过氧化程度（通过测量硫代巴比妥酸反应性物质如丙二醛的水平）以及正常超微结构改变。第二组15只大鼠未发生脊髓损伤，仅行椎板切除术以确定手术对生化指标和改变的影响。第三组15只大鼠腹腔注射生理盐水，其量等同于脊髓损伤后立即给予的纳洛酮量。第四组15只大鼠在损伤后立即腹腔注射单次剂量0.5 mg纳洛酮，并在损伤后60分钟再次注射。脊髓损伤后Na(+)-K+/Mg+2 ATPase活性迅速降低，且在损伤后120分钟内一直低于第一组和第二组的水平。创伤后立即给予纳洛酮治疗可减轻Na(+)-K+/Mg+2 ATPase的失活。另一方面，第一组和第三组动物的丙二醛含量存在显著差异。纳洛酮治疗降低了第四组的丙二醛含量。（摘要截断于250字）
