Comparison of 1-hour and 24-hour blood pressure recordings in central or peripheral baroreceptor-denervated rats.
Comparison of 1-hour and 24-hour blood pressure recordings in central or peripheral baroreceptor-denervated rats.
复制标题
中枢或外周压力感受器去神经支配大鼠 1 小时和 24 小时血压记录的比较。
作者：
R. Buchholz;J. Hubbard;M. Nathan
我们比较了清醒的，不受约束的大鼠在1小时和24小时的连续记录会议期间，3至4周后，无论是sinoartic去神经，放置电解损伤孤束核，或假手术的平均动脉压和心率活动。去窦弓神经和孤束核损伤都消除了反射性心动过缓苯肾上腺素引起的升压反应。各组1小时和24小时记录的平均动脉压平均水平和不稳定性均无差异。没有观察到孤束核病变大鼠的平均动脉压升高，尽管在一半的去窦房神经大鼠中观察到轻度高血压，而另一半血压正常。未发现心率或心率变异性的组间差异;然而，所有组的24小时记录值均显著高于1小时记录值。延髓病变和窦主动脉去神经显着增加平均动脉压的不稳定性，但增加的幅度显着更大的病变大鼠。在sinocentic-denervated大鼠的平均动脉压的不稳定性在很大程度上取决于运动相关的降压反应，产生负偏的平均动脉压的频率分布。孤束核病变的大鼠表现出升压和降压反应，导致压力分布有轻微的正偏斜，类似于对照组大鼠显示。它的结论是，短期连续记录的平均动脉压和心率准确地估计改变的心血管活动的压力感受器去神经大鼠。中枢和外周压力感受器失神经大鼠心血管反应的差异被认为是由于孤束核病变对中枢神经元和参与心血管调节的通路的更广泛的破坏。
We compared the mean arterial pressure and heart rate activity of conscious, unrestrained rats during 1-hour and 24-hour continuous recording sessions, 3 to 4 weeks after either sinoartic denervation, placement of electrolytic lesions in the nucleus tractus solitarii, or sham operations. Sinoaortic denervation and nucleus tractus solitarii lesions both eliminated the reflex bradycardia to a phenylephrine-induced pressor response. No difference was found in the average level and lability of the mean arterial pressure between 1-hour and 24-hour recordings for any group. No elevation in the average mean arterial pressure of rats with nucleus tractus solitarii lesions was observed, although a mild hypertension was noted in half the sinoarotic-denervated rats, while the other half were normotensive. Group differences were not found for heart rate or heart rate variability; however, 24-hour recordings yielded significantly higher values than 1-hour recordings for all groups. Both medullary lesions and sinoaortic denervation significantly increased the lability of the mean arterial pressure, but the magnitude of the increase was significantly greater in the rats with lesions. The lability of the mean arterial pressure in sinoaortic-denervated rats depended largely on movement-related depressor responses that produced a negative skew in the frequency distribution of their mean arterial pressure. Rats with nucleus tractus solitarii lesions exhibited both pressor and depressor responses that resulted in pressure distributions that had a slight positive skew similar to that displayed by control rats. It is concluded that short-term continuous recordings of mean arterial pressure and heart rate accurately estimate the altered cardiovascular activity of baroreceptor-denervated rats. The differences in the cardiovascular responses of central and peripheral baroreceptor-denervated rats are believed to be due to the more extensive destruction by nucleus tractus solitarii lesions of central neurons and pathways involved in cardiovascular regulation.