高位胸段硬膜外阻滞对原发性高血压合并左心室肥大老年病人淋巴细胞β1-ARK mRNA表达的影响

Effect of high thoracic epidnral block on expression of β1-ARK mRNA in lymphocytes in elderly patients with essential hypertension complicated with left ventricular hypertrophy

目的探讨高位胸段硬膜外阻滞（HTEB）对原发性高血压合并左心室肥大老年病人淋巴细胞β1肾上腺素能受体激酶（β1-ARK）mRNA表达的影响。方法拟行胃大部切除术的原发性高血压合并左心室肥大病人20例，性别不限，ASAⅡ或Ⅲ级，年龄65～75岁，随机分为2组（n=10）：静吸复合全麻组（Ⅰ组）和HTEB＋静吸复合全麻组（Ⅱ组）。Ⅱ组经L6,7间隙行硬膜外穿刺，采用罗哌卡因行HTEB，至术后72h；Ⅰ组术后72h内行芬太尼病人自控静脉镇痛。于入室30min（基础状态）、意识完全恢复时（T1）、术后第1天（T2）、第3天（T3）及第5天（T4）记录心率变异性（HRV）各指标：总功率（TP）、高频功率（HF）、低频功率（LF），并计算LF／HF；同时行视觉模拟评分（VAS），评价疼痛程度；测定淋巴细胞β1-ARK mRNA及其底物β1-arrestin mRNA的表达水平。结果两组各时点VAS评分差异无统计学意义（P〉0．05）；与Ⅰ组比较，Ⅱ组术后TP、HF、LF和LF／HF升高，淋巴细胞β1-ARK mRNA表达下调（P〈0．05或0．01），β1-arrestin mRNA表达差异无统计学意义（P〉0．05）；与T1时比较，两组T2时TP升高、HF降低，β1-ARK mRNA表达上调（P〈0．05），其余时点差异无统计学意义（P〉0．05）。围术期TP与淋巴细胞β1-ARK mRNA表达水平呈负相关（r=-0．520，P〈0．01）。结论HTEB可有改善原发性高血压合并左心室肥大老年病人上腹部手术围术期的心脏自主神经调节功能，其机制与抑制β1-ARK mRNA表达上调有关。

Objective To investigate the effect of high thoracic epidural block （HTEB） on the expression of β-adrenergic receptor kinase-1 （β1-ARK） mRNA in the lymphocytes in the elderly patients with essential hypertension complicated with left ventricular hypertrophy （LVH）. Methods Twenty ASA Ⅱ or Ⅲ elderly patients with essential hypertension complicated with LVH scheduled for subtotal gastrectomy under general anesthesia were randomly divided into 2 groups （n = 10 each）： intravenous-inhalational anesthesia group （group Ⅰ ） and HTEB combined with intravenous-inhalational anesthesia group （group Ⅱ ）. In group Ⅱ , epidural anesthesia was performed at T6.7 and ropivacaine was infused until 72 h after operation for HTEB. In group Ⅰ , patient-controlled intravenous analgesia （PCIA） was performed with fentanyl in 72 h after operation. The heart rate variability （HRV） parameters, including total power （TP）, high frequency （HF） power and low frequency （LF） power, were recorded 30 min after entering the operating room （baseline）, at the recovery time of consciousness （T1 ）, and on 1st, 3rd and 5th day after operation （T2-4 ）,and LF/HF was calculated. VAS scores were recorded and the severity of pain was assessed. The blood samples were drawn from the right internal jugular vein at the time points mentioned above for determination of β1-ARK mRNA and β1-arrestin mRNA expression. Results There were no significant differences in VAS scores at each time point between two groups （ P 〉 0.05） . TP, HF, LF and LF/HF were significantly increased, and β1 -ARK mRNA expression was down-regulated after operation in group Ⅱ compared with group Ⅰ （P 〈 0.05 or 0.01）, but there was no significant difference in β1-arrestin mRNA expression between group Ⅰ and Ⅱ （ P 〉 0.05） . TP was significantly increased, HF significantly decreased, and β1 -ARK mRNA expression up-regulated in two groups at T2 compared with those at T1 （ P 〈 0.05 ）, but no significant difference was found at the other time points （P 〉 0.05 ）. TP was inversely correlated with the expression of β1-ARK mRNA in the lymphocytes during the perioperative period using Pearson correlation analysis （ r = - 0. 520, P 〈 0.01 ）. Conclusion HTEB can maintain the balance of the autonomic nervous system and improve HRV during upper abdominal surgery in the elderly patients with essential hypertension complicated with LVH, and the mechanism is related to the up-regulation of β1 -ARK mRNA expression.