Rossberg F, Martinez L
Eur J Appl Physiol Occup Physiol. 1983;50(2):291-300. doi: 10.1007/BF00422168.
The initial heart rate response to rapid passive changing of posture was analysed in 43 normal subjects. The tilting (mean tilt time: 1.7 s) was applied during expiration or inspiration. As compared to inspiration, the 70 degrees head-up tilt during expiration resulted in significantly higher values of heart rate increase and longer duration of the "initial complex", i.e. the immediate increase and the following decrease of heart rate to a minimum after tilting. The heart rate response to tilting from erect to supine position was not symmetrical to that during head-up tilt: at first the heart rate increased, about 6 s after the change of body position heart rate decreased suddenly, mostly below the recumbent control value, which was attained again after about 20-30 s. The distinct initial heart rate response to the head-up tilt probably can be explained in part by the hydrostatically caused drop of the mural pressure at the level of carotid artery and the different sensitivity of arterial baroreflex during the respiratory cycle. Other mechanisms, e.g. the participation of chronotropic autoregulation are discussed.
对43名正常受试者进行了分析，观察其在姿势快速被动改变时的初始心率反应。倾斜（平均倾斜时间：1.7秒）在呼气或吸气时进行。与吸气相比，呼气时70度头高位倾斜导致心率增加的值显著更高，且“初始复合体”的持续时间更长，即倾斜后心率立即增加并随后降至最低值。从直立位到仰卧位倾斜时的心率反应与头高位倾斜时不对称：起初心率增加，体位改变约6秒后心率突然下降，大多低于卧位对照值，约20 - 30秒后再次达到该值。头高位倾斜时明显的初始心率反应可能部分是由于颈动脉水平的静水压导致壁压力下降以及呼吸周期中动脉压力反射的不同敏感性所致。还讨论了其他机制，如变时性自身调节的参与情况。
