Suzuki J, Gao M, Yahata T, Kuroshima A, Koyama T
Laboratory of Sports Physiology, Hokkaido University of Education, Japan.
Acta Physiol Scand. 1997 Jul;160(3):243-50. doi: 10.1046/j.1365-201X.1997.00136.x.
The effects of chronic cold exposure on soleus muscle capillarity were examined, particularly in terms of the distribution of arteriolar and venular capillaries and their capillary domain area (CDA) in adult rats exposed to cold for 68 generations (CG; n = 6). These parameters were compared with those obtained from control rats (CON; n = 5) and deacclimatized rats (DCG; n = 4), reared in thermoneutral temperature after being reared for 11 generations in cold. Morphometric data were obtained from muscle cross sections exposed to a double-staining method that stained the arteriolar and venular portions of capillaries blue and red, respectively. In CG, the capillary densities of arteriolar and venular capillaries were significantly greater than that of both CON and DCG (P < 0.05). The CDA of arteriolar, intermediate and venular portions in CG was significantly smaller by 15, 14 and 13%, respectively, than those of respective portions in CON (P < 0.05). Although CDA of arteriolar and venular capillary portions was also smaller in DCG than in CON, the degree of reduction was less in DCG than in CG. The succinate dehydrogenase activity of soleus muscle was significantly greater in CG than in both CON and DCG (P < 0.05). These results suggest that adaptive changes in the oxygen transport system, identified as an increase in the number of arteriolar capillaries and a reduction in the diffusion distance for oxygen, were observed in the soleus muscle after chronic cold exposure. These changes may improve the effective oxygen supply to muscle tissues and enable muscle tissues to promote thermogenesis in the cold atmosphere.
研究了长期冷暴露对成年大鼠比目鱼肌毛细血管的影响，特别是在连续68代（CG；n = 6）暴露于寒冷环境的大鼠中，小动脉和小静脉毛细血管的分布及其毛细血管领域面积（CDA）。将这些参数与对照组大鼠（CON；n = 5）和脱适应大鼠（DCG；n = 4）的参数进行比较，后者在寒冷环境中饲养11代后，在热中性温度下饲养。形态学数据取自经双重染色法处理的肌肉横截面，该方法分别将毛细血管的小动脉和小静脉部分染成蓝色和红色。在CG组中，小动脉和小静脉毛细血管的密度显著高于CON组和DCG组（P < 0.05）。CG组中小动脉、中间和小静脉部分的CDA分别比CON组相应部分显著小15%、14%和13%（P < 0.05）。虽然DCG组中小动脉和小静脉毛细血管部分的CDA也比CON组小，但DCG组的减少程度小于CG组。CG组比目鱼肌的琥珀酸脱氢酶活性显著高于CON组和DCG组（P < 0.05）。这些结果表明，长期冷暴露后，比目鱼肌中观察到了氧运输系统的适应性变化，表现为小动脉毛细血管数量增加和氧扩散距离缩短。这些变化可能会改善肌肉组织的有效氧供应，并使肌肉组织在寒冷环境中促进产热。
