Montero David, Dandanell Sune, Oberholzer Laura, Keiser Stefanie, Breenfeldt-Andersen Andreas, Haider Thomas, Merlini Mario, Meinild-Lundby Anne-Kristine, Lundby Carsten
1 Zurich Center for Integrative Human Physiology (ZIHP), Institute of Physiology, University of Zurich, Zurich, Switzerland.
2 University Heart Center, Department of Cardiology, University Hospital Zurich, Zurich, Switzerland.
Vasc Med. 2017 Aug;22(4):285-291. doi: 10.1177/1358863X17712103. Epub 2017 Jun 23.
Arterial distensibility, an independent predictor of cardiovascular events, is transiently increased with acute hyperglycemia (AHG) in healthy individuals. Whether this response interacts with physical inactivity remains unknown. We examined the effects of short-term bed rest (BR) on the response of carotid artery distensibility (CD) to AHG, and the influence of underlying changes in insulin resistance and blood volume. CD was assessed with ultrasonography before as well as 30 and 120 minutes following ingestion of 75 g of glucose prior to and after 3 days of BR in 15 healthy male volunteers. Plasma insulin/glucose concentrations and blood volumes were concomitantly determined. On day 4 of BR, blood volume was re-established to pre-BR levels by albumin infusion and CD and insulin/glucose concentrations were determined as in the previous experimental days. Basal CD was not affected by BR. AHG increased CD before and after BR but reached a higher peak increment after BR (12% vs 60% at 30 min OGTT, p=0.028). BR also increased the plasma insulin concentration during AHG ( p=0.007). In regression analyses, plasma insulin and glucose concentrations were positively correlated to CD, particularly after BR ( r=0.31, p<0.05). Restoration of the BR-induced loss (5%) in blood volume did not affect the response of CD to AHG. In conclusion, short-term physical inactivity strongly accentuates the initial increase in CD in response to AHG in healthy individuals. This effect is associated with concomitant increases in circulating insulin concentration attributable to early insulin resistance.
动脉扩张性是心血管事件的一个独立预测指标，在健康个体中，急性高血糖（AHG）会使其短暂升高。这种反应是否与身体活动不足相互作用尚不清楚。我们研究了短期卧床休息（BR）对颈动脉扩张性（CD）对AHG反应的影响，以及胰岛素抵抗和血容量潜在变化的影响。在15名健康男性志愿者进行3天BR前后，在摄入75克葡萄糖之前以及之后30分钟和120分钟，用超声检查评估CD。同时测定血浆胰岛素/葡萄糖浓度和血容量。在BR的第4天，通过输注白蛋白将血容量恢复到BR前的水平，并像之前的实验日一样测定CD和胰岛素/葡萄糖浓度。基础CD不受BR影响。AHG在BR前后均增加了CD，但BR后达到更高的峰值增量（在30分钟口服葡萄糖耐量试验时分别为12%和60%，p=0.028）。BR还增加了AHG期间的血浆胰岛素浓度（p=0.007）。在回归分析中，血浆胰岛素和葡萄糖浓度与CD呈正相关，尤其是在BR后（r=0.31，p<0.05）。恢复BR引起的5%血容量损失并未影响CD对AHG的反应。总之，短期身体活动不足会强烈加剧健康个体对AHG的CD初始增加。这种效应与早期胰岛素抵抗导致的循环胰岛素浓度同时增加有关。
