右美托咪定对脑缺血性损伤的保护作用

Neuroprotection by dexmedetomidine in cerebral ischemia

右美托咪定是一种新型的高选择性肾上腺素α_2受体激动药,可作为神经外科患者围术期的镇静药和麻醉辅助用药。右美托咪定对缺血性脑损伤的保护作用已在动物脑缺血模型中得到证实,其可减少脑血流,对脑血流动力学和颅内压无不良影响,具有良好的安全性。其脑保护机制包括抑制儿茶酚胺释放、减轻兴奋性氨基酸的毒性、抑制神经元凋亡。右美托咪定是否可作为脑保护药物用于减轻神经外科患者围术期由于脑缺血所导致的继发性脑损害,改善患者神经系统功能预后及其具体的生理级联反应关系有待进一步研究。

Dexmedetomidine is a new adrenoceptor agonist with high specificity to α2-receptor. In clinical practice, dexmedetomidine has been used as perioperative sedatives and adjuvant anesthetics for neurosurgical patients. Its neuroprotective effect during cerebral ischemic has been evidenced in laboratory experiments. Dexmedetomidine can reduce cerebral blood flow, and has no adverse effects on cerebral hemodynamics and intracranial pressure. The possible neuroprotective mechanisms of dexmedetomidine include inhibition of eateeholamine release, reducing the toxicity of excitatory amino acids, and inhibition of neuronal apoptosis. But as a potential neuroproteetant, whether dexmedetomidine can improve the outcome of neurologieal patients induced by perioperative cerebral isehemia and their speeifie physiological cascade of action need further studies.