Regulation of blood oxygen transport and red cell pHi after exhaustive activity in rainbow trout (Salmo gairdneri) and starry flounder (Platichthys stellatus).
Regulation of blood oxygen transport and red cell pHi after exhaustive activity in rainbow trout (Salmo gairdneri) and starry flounder (Platichthys stellatus).
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虹鳟鱼 (Salmo gairdneri) 和星状比目鱼 (Platichthys stellatus) 力竭活动后血氧运输和红细胞 pHi 的调节。
DOI：
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发表时间：
1987
影响因子：
2.8
通讯作者：
C. Wood
中科院分区：
文献类型：
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作者：
C. Milligan;C. Wood
在体外，外源性肾上腺素减少玻尔和根移位所造成的升高的PaCO 2和血浆pH值降低虹鳟鱼的血液，但不是在星比目鱼的血液。在体内，运动后立即，血浆肾上腺素（Ad）和去甲肾上腺素（NAd）增加约12倍，虹鳟鱼。与这种儿茶酚胺动员相关的是显着的血液浓缩、红细胞（RBC）肿胀和RBC [NTP]减少;后者大于单独由细胞肿胀解释的结果，表明三磷酸核苷（NTP）的代谢降解。RBC细胞内pH值（pHi）仅略有下降运动后（0.07个单位）在0小时，但恢复了0.5小时，在面对一个大的血浆酸中毒（0.4个单位）。[O2]/[Hb]显著下降，但这种下降可能部分归因于PaO 2的显著降低。在[O2]/[Hb]的减少低于预测从体外O2-解离曲线在低（0.5 nmol L-1）的儿茶酚胺水平，但类似于预测在高（90 nmol L-1）的儿茶酚胺水平。在比目鱼中，休息时的Ad和NAd水平约为鳟鱼的10倍，运动后没有明显变化。因此，RBC [NTP]没有减少，RBC pHi在运动后面对大量血浆酸中毒（0.4单位）显著下降（0.10单位），并保持抑制直至4小时，尽管确实发生了RBC肿胀。在PaO 2恒定的情况下，除了PaCO 2增加外，这些因素可能导致动脉[O2]/[Hb]降低。然而，在校正RBC pHi和PaCO 2之前，[O2]/[Hb]恢复到静息水平。这一点，结合观察，儿茶酚胺并没有影响在体外血液-O2解离曲线，表明其他因素可能参与调节运动后的比目鱼O2运输。
In vitro, exogenous adrenaline reduced the Bohr and Root shifts caused by elevated PaCO2 and depressed plasma pH in rainbow trout blood, but not in starry flounder blood. In vivo immediately after exercise, plasma adrenaline (Ad) and noradrenaline (NAd) increased about 12-fold in rainbow trout. Associated with this catecholamine mobilization was a significant haemoconcentration, red blood cell (RBC) swelling and a reduction in RBC [NTP]; the latter was larger than that explained by cell swelling alone, indicating metabolic degradation of nucleoside triphosphate (NTP). RBC intracellular pH (pHi) fell only slightly after exercise (0.07 units) at 0 h, but was restored by 0.5 h in the face of a large plasma acidosis (0.4 units). [O2]/[Hb] fell significantly, but this decline may have been due in part to the significant reduction in PaO2. The reduction in [O2]/[Hb] was less than predicted from in vitro O2-dissociation curves at low (0.5 nmol l-1) catecholamine levels, but similar to that predicted at high (90 nmol l-1) catecholamine levels. In flounder, resting Ad and NAd levels were about 10 times those in trout and did not change significantly after exercise. As a consequence, there was no reduction in RBC [NTP], and RBC pHi fell significantly (0.10 units) after exercise in the face of a large plasma acidosis (0.4 units) and remained depressed until 4 h, although RBC swelling did occur. These factors in addition to the increased PaCO2 may have contributed to the reduction in arterial [O2]/[Hb], in the face of a constant PaO2. However, [O2]/[Hb] was restored to resting levels prior to the correction of RBC pHi and PaCO2. This, in conjunction with the observation that catecholamines did not affect the in vitro blood--O2 dissociation curve, suggests that additional factors may be involved in regulating O2 transport after exercise in flounder.