van Baak M A, Mooij J M, Wijnen J A
Department of Human Biology, University of Limburg, Maastricht, The Netherlands.
Int J Sports Med. 1993 Jan;14(1):2-8. doi: 10.1055/s-2007-1021137.
Inhibition of adipose tissue lipolysis, leading to a reduced availability of non-esterified fatty acids for energy production in the active skeletal muscles, may be involved in the impairment of endurance exercise capacity after administration of a beta-adrenoceptor blocking agent. The effect of increasing the availability of plasma NEFA during exercise after beta-blocker administration was studied. In a double-blind, randomized cross-over study 12 healthy volunteers were treated for 14 days with placebo, atenolol, and propranolol. On the 7th and 14th day of each treatment period an endurance exercise test at 70% of maximal aerobic power until exhaustion was performed while a continuous infusion of saline or triglycerides (Intralipid)+heparin was administered. Endurance time was reduced by 11% (n.s.) during atenolol and 40% (p < 0.01) during propranolol. Intralipid administration had no statistically significant effect on endurance in any treatment. Plasma NEFA and glycerol concentrations were elevated above control levels during Intralipid infusion, plasma glucose and lactate concentrations were unaffected. These results suggest that reduced availability of NEFA is not a major factor in the reduction of endurance performance during beta-adrenoceptor blockade, although an effect of beta-blockade on NEFA membrane transport cannot be excluded.
脂肪组织脂解作用受到抑制，导致活跃的骨骼肌中用于能量产生的非酯化脂肪酸可用性降低，这可能与给予β-肾上腺素能受体阻滞剂后耐力运动能力受损有关。研究了在给予β-阻滞剂后运动期间增加血浆非酯化脂肪酸（NEFA）可用性的影响。在一项双盲、随机交叉研究中，12名健康志愿者分别接受安慰剂、阿替洛尔和普萘洛尔治疗14天。在每个治疗期的第7天和第14天，进行一次以最大有氧功率的70%进行的耐力运动测试，直至力竭，同时持续输注生理盐水或甘油三酯（英脱利匹特）+肝素。阿替洛尔治疗期间耐力时间减少了11%（无统计学意义），普萘洛尔治疗期间减少了40%（p<0.01）。英脱利匹特给药对任何治疗的耐力均无统计学显著影响。在输注英脱利匹特期间，血浆NEFA和甘油浓度升高至高于对照水平，血浆葡萄糖和乳酸浓度未受影响。这些结果表明，尽管不能排除β-阻滞剂对NEFA膜转运的影响，但NEFA可用性降低不是β-肾上腺素能受体阻滞剂阻断期间耐力表现降低的主要因素。
