Golding E M, Bryan R M, Golding R M
Department of Anesthesiology, Baylor College of Medicine, Houston, TX 77030, USA.
Physiol Meas. 2002 Nov;23(4):615-28. doi: 10.1088/0967-3334/23/4/302.
This paper evolves from our previous work that developed a blood vessel model based on the way in which the total tension within the blood vessel wall varies with pressure due to the interaction of specific ions. We use the previous outcomes to examine the diameter of rat middle cerebral arteries (MCAs) as a function of pressure. The MCAs were isolated at 2 h, 1 and 5 days following sham injury and severe traumatic brain injury (TBI). First, we are able to quantify the diameter versus pressure curve in a way that yields three parameters. One of these parameters is the diameter at zero pressure that incorporates properties of the blood vessel walls and the vascular smooth muscle cells. The other two parameters are associated with the myogenic response and the myogenic tone. These parameters enable us to characterize, from the MCAs as a function of pressure in a calcium buffer, each blood vessel into one of three distinct distributions. One of these distributions reflects the optimum conditions. From our data with our blood vessel model, we demonstrate the effect of sham injury on the way in which blood vessels respond to pressure change that appears to recover over time with a half-life of about 40 h. In contrast, severe TBI greatly affects the blood vessel with no indication of recovery over the five-day monitoring period.
本文源于我们之前的工作，该工作基于特定离子相互作用导致血管壁内总张力随压力变化的方式开发了一种血管模型。我们利用之前的研究结果来研究大鼠大脑中动脉（MCA）的直径随压力的变化情况。在假手术损伤和严重创伤性脑损伤（TBI）后的2小时、1天和5天分离出MCA。首先，我们能够以产生三个参数的方式量化直径与压力的曲线。其中一个参数是零压力下的直径，它包含了血管壁和血管平滑肌细胞的特性。另外两个参数与肌源性反应和肌源性张力有关。这些参数使我们能够根据MCA在钙缓冲液中随压力的变化，将每根血管分为三种不同分布类型之一。其中一种分布反映了最佳条件。根据我们血管模型的数据，我们证明了假手术损伤对血管对压力变化反应方式的影响，这种影响似乎会随着时间的推移以约40小时的半衰期恢复。相比之下，严重的TBI对血管有很大影响，在五天的监测期内没有恢复的迹象。
