目的 探讨右美托咪定辅助脑深部电刺激术对老年帕金森病患者环磷酸腺苷/蛋白激酶A（cAMP/PKA）信号通路的影响。 方法 选取2021年1月至2025年1月南京医科大学附属脑科医院收治的行脑深部电刺激术治疗的150例老年帕金森病患者作为研究对象，以随机数字表法将所选患者分为A组（75例）和B组（75例）。B组麻醉诱导前泵注右美托咪定，A组泵注相同体积生理盐水，均观察至术后2周，并进行为期6个月的随访。比较两组围术期相关指标，丘脑底核（STN）频率、双侧丘脑底核电生理信号长度、坐标误差，围手术期血流动力学［麻醉诱导前（T₀）、全身麻醉插管后（T₁）、麻醉加深时（T₂）］，脑损伤情况（术前1 h、术后1 d），Ramsay镇静评分（入手术室时、手术开始前、术中定位测试时、手术结束时），帕金森综合征评分量表运动评分（UPDRS）、认知功能、cAMP/PKA信号通路（术前1 h、术后2周）。 结果 手术、意识消失及自主呼吸恢复时间在B组明显较短（P < 0.05）。B组STN频率、双侧STN电生理信号长度、坐标误差与A组组间比，差异无统计学意义（P > 0.05）。T₀ ~ T₂两组MAP、HR均呈现逐渐降低趋势，T₁、T₂时刻B组平均动脉压（MAP）、心率（HR）高于A组，T₀ ~ T₂两组脑电双频指数（BIS）则呈现先降低后升高趋势（P < 0.05），两组间BIS、不同时刻及两组间血氧饱和度（SpO₂）比较，差异无统计学意义（P > 0.05）。较术前1 h，术后1 d两组血清中枢神经特异蛋白（S-100β）、神经元特异性烯醇化酶（NSE）、同型半胱氨酸（Hcy）水平均升高，但B组更低，血清尿酸（UA）水平则均降低，但B组更高（P < 0.05）。入手术室时至手术结束时，两组Ramsay镇静评分均呈现逐渐升高趋势，其中术中定位测试时和手术结束时B组Ramsay镇静评分高于A组（P < 0.05）。较术前1 h，术后2周单侧、双侧开关状态UPDRS评分均降低，其中B组更低（P < 0.05）。较术前1 h，术后2周两组蒙特利尔认知功能评估量表（MoCA）评分则均升高，B组更高（P < 0.05）。较术前1 h，术后2周两组血清cAMP、PKA水平均升高，B组更高（P < 0.05）。 结论 右美托咪定可稳定脑深部电刺激术治疗老年帕金森病患者围手术期血流动力学指标，调节cAMP/PKA信号通路，改善其脑损伤情况，同样具有良好靶点定位作用，缩短患者手术时间、意识消失时间及恢复时间，提高其镇静程度，提高患者认知功能及运动功能。

Objective To investigate the effect of dexmedetomidine-assisted deep brain stimulation on the cAMP/PKA signal pathway in elderly patients with Parkinson's disease. Methods A total of 150 elderly patients with Parkinson's disease who underwent deep brain stimulation （DBS） at the Affiliated Brain Hospital of Nanjing Medical University from January 2021 to January 2025 were selected as the study subjects. The enrolled patients were randomly divided into Group A （75 cases） and Group B （75 cases） using the random-number table method. In Group B， dexmedetomidine was pumped before anesthesia induction， while in Group A， an equal-volume of saline was pumped. The patients were observed for 2 weeks after the operation and followed up for 6 months. The perioperative-related indicators of the two groups were compared， including subthalamic nucleus （STN） frequency， length of bilateral subthalamic nucleus physiological signals， coordinate error， perioperative hemodynamics ［before anesthesia induction （T₀）， after general anesthesia intubation （T₁）， and during anesthesia deepening （T₂）］， brain injury indicators （1 h before surgery， 1 d after surgery）， Ramsay sedation score （before entering the operating room， before surgery， during intraoperative localization testing， and at the end of surgery）， motor score of the Parkinson's syndrome scoring scale （UPDRS）， cognitive function， and cAMP/PKA signaling pathway （1 h before surgery， 2 weeks after surgery）. Results The recovery times of operation， unconsciousness， and spontaneous breathing in Group B were significantly shorter （P < 0.05）. There were no significant differences in STN frequency， bilateral STN electrophysiological signal length， and coordinate error between Group B and Group A （P > 0.05）. The mean arterial pressure （MAP） and heart rate （HR） in the T₀ ~ T₂ groups showed a decreasing trend. At T₁ and T₂， the MAP and HR in Group B were higher than those in Group A. Meanwhile， the bispectral index （BIS） in the T₀ ~ T₂ groups showed a trend of first decreasing and then increasing （P < 0.05）. There were no significant differences in BIS and SpO₂ at different times and between the two groups （P > 0.05）. Compared with one hour before operation and one day after operation， the levels of serum central nervous system - specific protein （S - 100β）， neuron-specific enolase （NSE）， and homocysteine （Hcy） in both groups were higher， but these levels were lower in Group B. In contrast， the level of serum uric acid （UA） was lower overall， but it was higher in Group B （P < 0.05）. In both groups， the Ramsay sedation scores gradually increased from the time of entering the operating room until the end of the operation. At the time of the intraoperative localization test and the end of the operation， the Ramsay sedation scores in group B were significantly higher than those in group A （P < 0.05）. When compared to the scores 1 hour before the operation and 2 weeks after the operation， the Unified Parkinson's Disease Rating Scale （UPDRS） scores in both the unilateral and bilateral switch states were lower， with a more pronounced decrease in group B （P < 0.05）. Similarly， the scores on the Montreal Cognitive Assessment Scale （MoCA） in both groups were higher when compared to the pre-operation （1 hour before） and 2-week post-operation scores， particularly in group B （P < 0.05）. Moreover， the levels of serum cyclic adenosine monophosphate （cAMP） and protein kinase A （PKA） in both groups were higher compared to those 1 hour before the operation and 2 weeks after the operation， especially in group B （P < 0.05）. Conclusions Dexmedetomidine can stabilize the perioperative hemodynamic indexes， regulate the cAMP/PKA signaling pathway， and improve the indexes of brain injury in elderly patients with Parkinson's disease undergoing deep-brain stimulation. Additionally， dexmedetomidine exhibits a favorable target-positioning effect， which shortens the operation time， the time of consciousness disappearance， and the recovery time. It also enhances the degree of sedation and improves the cognitive and motor functions of patients.