Department of Clinical Laboratory Sciences, School of Health Sciences, Fukushima Medical University.
Department of Laboratory Medicine, Fukushima Medical University School of Medicine.
J Atheroscler Thromb. 2021 Dec 1;28(12):1340-1348. doi: 10.5551/jat.60848. Epub 2021 Mar 20.
The cardio-ankle vascular index (CAVI) consists of intrinsic and functional arterial stiffness mainly regulated by vasoactive compounds. A new stiffness index of the aorta (aBeta) and iliac-femoral arteries (ifBeta) was determined by applying the CAVI theory to the whole aorta and iliac-femoral arteries. We investigated the changes in aBeta and ifBeta in response to decreased blood pressure (BP) induced by the Ca channel blocker nicardipine to elucidate the involvement of Ca in aBeta and ifBeta.
Pressure waves at the origin of the aorta (oA), distal end of the abdominal aorta (dA), and left femoral artery (fA) as well as flow waves at the oA were simultaneously recorded before and after the infusion of nicardipine (50 µg/kg/min) for 2 min in 12 male rabbits under pentobarbital anesthesia. Beta was calculated using the following formula: Beta=2ρ / PP×ln (SBP / DBP)×PWV, where ρ, SBP, DBP, and PP denote blood density and systolic, diastolic, and pulse pressures, respectively. aBeta, ifBeta, and aortic-iliac-femoral Beta (aifBeta) were calculated using aPWV, ifPWV, and aifPWV, respectively.
SBP, mean arterial pressure (MAP), DBP, and total peripheral vascular resistance significantly decreased during the administration of nicardipine, whereas cardiac output significantly increased. aBeta and ifBeta significantly increased and decreased, respectively, whereas aifBeta did not change despite the decrease in BP. ifBeta and aBeta positively and negatively correlated with BP, respectively, whereas aifBeta did not correlate with SBP.
There were contradictory arterial responses to nicardipine between the elastic and muscular arteries. Unknown vasoconstriction mechanisms that are not involved in Ca influx may function in the aorta in response to decreased BP.
心血管踝动脉指数（CAVI）主要由血管活性化合物调节的内在和功能性动脉僵硬组成。通过将 CAVI 理论应用于整个主动脉和股髂动脉，确定了主动脉（aBeta）和股髂动脉（ifBeta）的新僵硬指数。我们研究了 aBeta 和 ifBeta 对硝苯地平（Ca 通道阻滞剂）诱导的血压（BP）降低的反应变化，以阐明 Ca 在 aBeta 和 ifBeta 中的作用。
在戊巴比妥麻醉下，12 只雄性兔静脉输注硝苯地平（50μg/kg/min）2 分钟，记录主动脉起始处（oA）、腹主动脉末端（dA）和左股动脉（fA）的压力波以及 oA 的血流波。使用以下公式计算β：β=2ρ / PP×ln（SBP / DBP）×PWV，其中 ρ、SBP、DBP 和 PP 分别表示血液密度、收缩压、舒张压和脉压。使用 aPWV、ifPWV 和 aifPWV 分别计算 aBeta、ifBeta 和主动脉-股髂 Beta（aifBeta）。
硝苯地平给药期间，收缩压、平均动脉压、舒张压和总外周血管阻力显著降低，心输出量显著增加。aBeta 和 ifBeta 分别显著增加和减少，而 aifBeta 尽管血压下降但没有变化。ifBeta 和 aBeta 与 BP 呈正相关和负相关，而 aifBeta 与 SBP 不相关。
弹性和肌性动脉对硝苯地平的动脉反应存在矛盾。在响应降低的 BP 时，可能存在不涉及 Ca 内流的未知血管收缩机制。
