Pelster B, Bridges C R, Grieshaber M K
Institut für Zoologie, Universität Düsseldorf, F.R.G.
Respir Physiol. 1988 Mar;71(3):355-73. doi: 10.1016/0034-5687(88)90028-x.
Gas exchange, metabolism, ventilation, circulation and acid-base balance in water and air were investigated in Blennius pholis. The rates of gas exchange in water and air were similar with the RQ remaining around 0.8. Aerial gas exchange was equally divided between the head/gills and the tail region. Ventilatory adaptations involved a reduction in rate in air and the mode of ventilation changed from flow-through to tidal, with closed opercula. A transient bradycardia developed on transition to air before heart frequency (fH) returned to aquatic levels. During aerial exposure PvCO2 rose only by 1 Torr with a concomitant decrease in pH of 0.19 pH-units. At the same time a metabolic acidosis was observed which could not be fully accounted for by the formation of lactic acid in the blood, although tissue lactate levels did not change significantly. No histological evidence was found for the presence of carbonic anhydrase in the epithelial cells of the skin or the oesophagus to aid aerial CO2 excretion. Inhibition of CA activity by addition of methazolamide to blood, however, caused PvCO2 to rise by 3 Torr and pHv to decrease by 0.4 pH unit. It is concluded that B. pholis is physiologically well adapted to aerial exposure through adjustments in ventilation and circulation and that erythrocytic carbonic anhydrase plays a major role in CO2 transfer.
对斑纹鳚的水和空气中的气体交换、代谢、通气、循环及酸碱平衡进行了研究。其在水和空气中的气体交换速率相似，呼吸商（RQ）保持在0.8左右。空气中的气体交换在头部/鳃和尾部区域之间平均分配。通气适应包括在空气中速率降低，通气模式从连续通气转变为潮式通气，鳃盖关闭。在过渡到空气时会出现短暂的心动过缓，之后心率（fH）恢复到水生时的水平。在空气暴露期间，静脉血二氧化碳分压（PvCO2）仅升高1托，同时pH值下降0.19个pH单位。与此同时，观察到代谢性酸中毒，尽管组织乳酸水平没有显著变化，但血液中乳酸的形成并不能完全解释这种情况。在皮肤或食道的上皮细胞中未发现碳酸酐酶存在的组织学证据来辅助空气中二氧化碳的排泄。然而，向血液中添加甲唑酰胺抑制碳酸酐酶（CA）活性会导致PvCO2升高3托，静脉血pH值（pHv）降低0.4个pH单位。得出的结论是，斑纹鳚通过通气和循环的调整在生理上很好地适应了空气暴露，并且红细胞碳酸酐酶在二氧化碳转运中起主要作用。
