Oosting J, Struijker-Boudier H A, Janssen B J
Department of Pharmacology, Universiteit Maastricht, The Netherlands.
J Hypertens. 1997 Apr;15(4):391-9. doi: 10.1097/00004872-199715040-00010.
To develop and validate a technique for the continuous computerized calculation of the baroreceptor reflex sensitivity (BRS) of the heart rate in rats.
The BRS was calculated from spontaneous changes in blood pressure and pulse interval using spectral analysis as well as time-series techniques. The BRS values obtained with these techniques were compared with those obtained by standard pharmacological methods.
The blood pressure and pulse interval in adult Wistar-Kyoto (WKY) rats were recorded on a beat-to-beat basis for two consecutive 30 min periods. During one of these periods the BRS was determined pharmacologically by injections of nitroprusside and phenylephrine. Measurements were performed after administration of saline as vehicle or during manipulation of the autonomic nervous system by infusion of metoprolol, methyl-atropine and hexamethonium. Sequential time-series methods for continuous BRS calculation were tested for 24 h periods in intact WKY rats as well as in WKY rats that had been subjected to sino-aortic denervation or to electrical lesioning of the nucleus tractus solitarius.
The correlation coefficient between BRS values in intact WKY rats derived from the pharmacological method and those from spectral analysis techniques was low (R2 = 0.16). The correlation coefficient between BRS values from the pharmacological method and those from the developed time-series method was higher (R2 = 0.64). The BRS measured using the latter method was found to vary over 24 h with the highest values during the sleeping period. After surgical elimination of the baroreflex, the algorithm returned BRS values close to zero throughout the 24 h period. The BRS estimate was found to be a measure of the parasympathetic rather than of the sympathetic component of the baroreceptor reflex.
The developed time-series method calculates an index of the gain of the cardiac baroreflex in rats faithfully. This method can be implemented in data acquisition software, allowing continuous on-line monitoring of the cardiac baroreflex gain.
开发并验证一种用于连续计算机化计算大鼠心率压力感受器反射敏感性（BRS）的技术。
使用频谱分析以及时间序列技术，根据血压和脉搏间期的自发变化计算BRS。将这些技术获得的BRS值与通过标准药理学方法获得的值进行比较。
连续两个30分钟时间段逐搏记录成年Wistar-Kyoto（WKY）大鼠的血压和脉搏间期。在其中一个时间段内，通过注射硝普钠和去氧肾上腺素以药理学方法测定BRS。在给予生理盐水作为赋形剂后或在通过输注美托洛尔、甲基阿托品和六甲铵对自主神经系统进行操作期间进行测量。在完整的WKY大鼠以及接受了窦主动脉去神经支配或孤束核电损伤的WKY大鼠中，对连续BRS计算的序贯时间序列方法进行了24小时的测试。
完整WKY大鼠中，药理学方法得出的BRS值与频谱分析技术得出的BRS值之间的相关系数较低（R2 = 0.16）。药理学方法得出的值与所开发的时间序列方法得出的值之间的相关系数较高（R2 = 0.64）。发现使用后一种方法测量的BRS在24小时内有所变化，睡眠期间的值最高。在通过手术消除压力反射后，该算法在整个24小时期间返回接近零的BRS值。发现BRS估计值是压力感受器反射的副交感神经而非交感神经成分的一种度量。
所开发的时间序列方法能够如实地计算大鼠心脏压力反射增益指数。该方法可在数据采集软件中实现，从而允许对心脏压力反射增益进行连续在线监测。
