Dabiré Hubert, Lacolley Patrick, Chaouche-Teyara Kamel, Fournier Berthe, Safar Michel E
Institut National de la Santé et de la Recherche Médicale, Paris, France.
J Cardiovasc Pharmacol. 2002 Jan;39(1):98-106. doi: 10.1097/00005344-200201000-00011.
The aim of this study was to determine in spontaneously hypertensive rats (SHRs) whether a significant association may be observed between the low-frequency component of blood pressure variability (BPV) and arterial distensibility and to evaluate the role of the autonomic nervous system in this relationship. Doxazosin (1 mg/kg/d s.c.), flesinoxan (1 mg/kg/d s.c.), and urapidil (30 mg/kg/d s.c.) were infused over 24 h in SHRs. Blood pressure was recorded in conscious rats and BPV was characterized by spectral analysis. The distensibility-pressure curves for the carotid artery were determined by an ultrasonic echo-tracking device in anesthetized rats. Untreated SHRs had higher mean arterial pressure (MAP) and low-frequency MAP but a lower distensibility than normotensive Wistar-Kyoto rats. In SHRs inhibition of the autonomic nervous system by peripheral blockade of alpha1-adrenoceptors (doxazosin, 1 mg/kg, or urapidil, 30 mg/kg) or centrally mediated reduction of sympathetic tone (flesinoxan, 1 mg/kg) reduced MAP and low-frequency MAP in the conscious state and increased carotid operational distensibility in the anesthetized state. In these SHRs, we observed a negative association between low-frequency MAP and operational distensibility ( r = -0.48, p < 0.01). From multiple regression analysis, MAP and low-frequency MAP, but not drug treatment, influenced arterial distensibility. Our study in SHRs provides evidence for a strong association between increased low-frequency MAP and reduced arterial distensibility, with a common modulation provided by the autonomic nervous system via the alpha 1 -adrenergic receptor component and central nervous system.
本研究的目的是确定在自发性高血压大鼠（SHR）中，血压变异性（BPV）的低频成分与动脉扩张性之间是否存在显著关联，并评估自主神经系统在这种关系中的作用。将多沙唑嗪（1毫克/千克/天，皮下注射）、氟西诺生（1毫克/千克/天，皮下注射）和乌拉地尔（30毫克/千克/天，皮下注射）在SHR中输注24小时。在清醒大鼠中记录血压，并通过频谱分析对BPV进行特征描述。在麻醉大鼠中，使用超声回声跟踪装置测定颈动脉的扩张性-压力曲线。未治疗的SHR比正常血压的Wistar-Kyoto大鼠具有更高的平均动脉压（MAP）和低频MAP，但扩张性更低。在SHR中，通过外周阻断α1肾上腺素能受体（多沙唑嗪，1毫克/千克，或乌拉地尔，30毫克/千克）或中枢介导的交感神经张力降低（氟西诺生, 1毫克/千克）来抑制自主神经系统，可降低清醒状态下的MAP和低频MAP，并增加麻醉状态下颈动脉的操作扩张性。在这些SHR中，我们观察到低频MAP与操作扩张性之间存在负相关（r = -0.48，p < 0.01）。多元回归分析表明，MAP和低频MAP而非药物治疗会影响动脉扩张性。我们对SHR的研究为低频MAP升高与动脉扩张性降低之间的强关联提供了证据，自主神经系统通过α1肾上腺素能受体成分和中枢神经系统提供了共同调节。
