Huxley V H, Williams D A, Meyer D J, Laughlin M H
Department of Physiology, University of Missouri School of Medicine, Columbia 65212, USA.
Acta Physiol Scand. 1997 Aug;160(4):315-25. doi: 10.1046/j.1365-201X.1997.00171.x.
Solute flux per unit surface area and concentration gradient, (J(S)/SdeltaC), was quantified in arterioles isolated from hearts of sedentary (SED) and exercise-trained (EX) female Yucatan Miniature Swine. Apparent permeability (P(S)) was assessed from measures of J(S)/SdeltaC for two proteins, alpha-lactalbumin (alpha-lact) and porcine serum albumin (PSA), under basal conditions and following 5 min suffusion with 10(-5) M adenosine (ADO). Both proteins were labelled with the fluorescent dye tetramethyl rhodamine isothiocyanate. Basal P(S) to alpha-lact differed with exercise training ((P(S)alpha-lact)SED = 5.2+/-1.8 (median+/-median absolute deviation (MAD), n = 9 pigs) versus (P(S)alpha-lact)EX = 7.4+/-1.1 x 10(-7) cm s(-1), n = 9, P < 0.05). For the larger protein PSA, basal P(S) did not change with training (P(S)PSA)SED = 50+/-1.6, N = 11 vs. (P(S)PSA)EX = 4.1+/-1.2 x 10(-7) cm s(-1), N = 11). Suffusion of the arterioles (33+/-4 microm diameter, n = 18 vessels) from SED hearts (n = 14) with 10(-5) M ADO decreased P(S)alpha-lact 15+/-8% relative to control and was without effect on P(S)PSA. By contrast, in arterioles (39+/-4 microm diameter, n = 22 vessels) from EX hearts (n = 14), ADO increased P(S)alpha-lact and P(S)PSA by 32 and 65% respectively, indicating that receptor-mediated changes in permeability were also sensitive to exercise training. These data demonstrate that, for coronary arterioles, permeability to macromolecules adapts to exercise training. The adaptive mechanisms may involve more than one structural component of the vessel wall as the changes in permeability were size-dependent.
在从久坐不动（SED）和运动训练（EX）的雌性尤卡坦小型猪心脏分离出的小动脉中，对单位表面积溶质通量和浓度梯度（J(S)/SδC）进行了量化。在基础条件下以及用10(-5) M腺苷（ADO）灌注5分钟后，根据两种蛋白质α-乳白蛋白（α-lact）和猪血清白蛋白（PSA）的J(S)/SδC测量值评估表观渗透率（P(S)）。两种蛋白质均用荧光染料异硫氰酸四甲基罗丹明标记。基础条件下，运动训练使α-乳白蛋白的P(S)有所不同（(P(S)α-lact)SED = 5.2±1.8（中位数±中位数绝对偏差（MAD），n = 9头猪），而(P(S)α-lact)EX = 7.4±1.1×10(-7) cm s(-1)，n = 9，P < 0.05）。对于较大的蛋白质PSA，基础条件下P(S)并未随训练而改变（(P(S)PSA)SED = 50±1.6，N = 11，对比(P(S)PSA)EX = 4.1±1.2×10(-7) cm s(-1)，N = 11）。用10(-5) M ADO灌注SED心脏（n = 14）的小动脉（直径33±4微米，n = 18条血管），相对于对照，P(S)α-lact降低了15±8%，且对P(S)PSA无影响。相比之下，在EX心脏（n = 14）的小动脉（直径39±4微米，n = 22条血管）中，ADO使P(S)α-lact和P(S)PSA分别增加了32%和65%，表明受体介导的渗透率变化也对运动训练敏感。这些数据表明，对于冠状动脉小动脉，对大分子的渗透率会适应运动训练。由于渗透率变化与大小有关，适应性机制可能涉及血管壁的多个结构成分。
