Zatz R
Nephrology Unit, University of São Paulo Medical School, Brazil.
Lab Anim Sci. 1990 Mar;40(2):198-201.
Methods utilized in the determination of systolic tail-cuff pressure (TCP) in awake rats are aimed at detecting the earliest possible tail pulsations as the cuff is deflated. In the method described in this study, a small, inexpensive electret microphone is used as a sensor, connected to the tail by a piece of rubber tubing. This design provides selective attenuation of tail pulsations appearing as the cuff is deflated between systolic and mean arterial pressures. In this manner, tail pulsations are detected only when the cuff pressure is lowered below the mean arterial pressure, thus providing an estimation of the latter. The method was validated in prewarmed awake normotensive and hypertensive rats by simultaneous comparison with directly measured systolic and mean pressures or with a conventional tail-cuff method. Validation studies were also carried out in anesthetized rats undergoing wide variations of arterial pressure by parenteral injections of norepinephrine or nitroprusside. Close agreement was observed between TCP determined with this method and directly obtained mean, but not systolic, pressure. Thus, the method described in this study constitutes an inexpensive alternative to conventional tail-cuff methods. Mean, rather than systolic pressure, appears to be evaluated in the conscious rat by employing this method.
测定清醒大鼠收缩期尾袖带血压（TCP）所采用的方法旨在检测袖带放气时最早出现的尾动脉搏动。在本研究描述的方法中，一个小型、廉价的驻极体麦克风被用作传感器，通过一段橡胶管连接到尾巴上。这种设计可对在收缩压和平均动脉压之间袖带放气时出现的尾动脉搏动进行选择性衰减。通过这种方式，仅当袖带压力降至平均动脉压以下时才检测到尾动脉搏动，从而对平均动脉压进行估计。通过与直接测量的收缩压和平均压或与传统尾袖带法同时比较，在预温清醒的正常血压和高血压大鼠中对该方法进行了验证。还通过静脉注射去甲肾上腺素或硝普钠使动脉压大幅波动，在麻醉大鼠中进行了验证研究。观察到用该方法测定的TCP与直接获得的平均压（而非收缩压）之间有密切一致性。因此，本研究描述的方法是传统尾袖带法的一种廉价替代方法。采用这种方法似乎能在清醒大鼠中评估平均压而非收缩压。
