Risberg J, Hordnes C, Tyssebotn I
Department of Physiology, University of Bergen, Norway.
Scand J Clin Lab Invest. 1987 Oct;47(6):521-7. doi: 10.1080/00365518709168463.
The acute effects of the beta 1-adrenoceptor inhibition by atenolol were investigated on conscious rats. Cardiac output and organ blood flow were measured by 15-microns radiolabelled microspheres during control and 20 min after administration of atenolol (1 mg/kg body wt). Arterial blood pressure and heart rate were measured continuously. Arterial blood gases and pH were determined immediately after the two microsphere injections and arterial blood samplings. The mean arterial blood pressure fell significantly shortly after the injection of atenolol and was reduced by 9% (p less than 0.02) after 20 min. Heart rate fell by 17% (p less than 0.05). The total peripheral vascular resistance increased by 25% (p less than 0.05). At the same time the arterial acid-base chemistry remained unaltered from the control. The cardiac output fell by 24% (p less than 0.05). Blood flow fell to all organs and tissues (0-67%) except to the brain, adrenals, liver, ears and diaphragm. The greatest decrease was seen in perfusion of the adipose tissue (67%) and of the spleen (60%), indicating that the blood flow to these organs are normally highly influenced by beta 1-adrenoceptor stimulation. The estimated work load of the heart was reduced by 20% which correlated well to a reduction of myocardial blood flow to the same degree.
研究了阿替洛尔对清醒大鼠β1 -肾上腺素能受体抑制的急性效应。在对照期以及给予阿替洛尔（1毫克/千克体重）20分钟后，用15微米放射性标记微球测量心输出量和器官血流量。连续测量动脉血压和心率。在两次微球注射和动脉采血后立即测定动脉血气和pH值。注射阿替洛尔后不久，平均动脉血压显著下降，20分钟后降低了9%（p＜0.02）。心率下降了17%（p＜0.05）。总外周血管阻力增加了25%（p＜0.05）。与此同时，动脉酸碱化学指标与对照期相比未发生改变。心输出量下降了24%（p＜0.05）。除脑、肾上腺、肝脏、耳朵和膈肌外，所有器官和组织的血流量均下降（0 - 67%）。脂肪组织（67%）和脾脏（60%）的灌注下降最为明显，表明这些器官的血流量通常受β1 -肾上腺素能受体刺激的高度影响。心脏的估计工作负荷降低了20%，这与心肌血流量的同等程度减少密切相关。
