PCO2 measurements in surface proximal tubules and peritubular capillaries of the rat kidney.
PCO2 measurements in surface proximal tubules and peritubular capillaries of the rat kidney.
复制标题
大鼠肾脏表面近端肾小管和肾小管周围毛细血管的 PCO2 测量。
DOI：
10.1152/ajprenal.1982.242.1.f78
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发表时间：
1982
期刊：
影响因子：
--
通讯作者：
Cohen,JJ
中科院分区：
文献类型：
--
作者：
Gennari,FJ;Caflisch,CR;Johns,C;Maddox,DA;Cohen,JJ
在正常酸碱条件下和三种HCO3（-）再吸收减少的情况下，分别测量大鼠表面近端小管和小管周围毛细血管的PCO2浓度：苯并胺给药、呼吸性碱中毒和代谢性酸中毒。正常情况下，早期近端小管（EP）的PCO2比PaCO2高10.5 mmHg (P < 0.001)，比晚期近端（LP）和小管周围毛细血管（PC）的PCO2高3-4 mmHg （P < 0.001）。LP和PC的PCO2比PaCO2高7 mmHg （P < 0.001）。苯并胺（3mg /kg）对动脉血PCO2和EP与动脉血PCO2的差异无影响。将苯甲酰胺增加到8 mg/kg时，相对于动脉PCO2，表面结构中的PCO2增加了3 ~ 5 mmHg （P < 0.01）。代谢性酸中毒没有改变皮质和动脉PCO2之间的关系。相比之下，呼吸性碱中毒使皮质PCO2相对于PaCO2降低了50%以上。EP PCO2仍高于LP和PC PCO2 （P < 0.01）。因此，减少HCO3（-）重吸收并不能消除EP与LP或PC PCO2之间的差异，也不能降低肾脏表面结构中相对于动脉PCO2的PCO2。
PCO2 was measured in surface proximal tubules and peritubular capillaries in the rat under normal acid-base conditions and in three settings with decreased HCO3(-) reabsorption: benzolamide administration, respiratory alkalosis, and metabolic acidosis. Under normal conditions, PCO2 in the early proximal tubule (EP) was 10.5 mmHg higher than PaCO2 (P less than 0.001) and 3-4 mmHg higher than late proximal (LP) and peritubular capillary (PC) PCO2 (P less than 0.001). PCO2 in LP and PC was 7 mmHg higher than PaCO2 (P less than 0.001). Benzolamide (3 mg/kg) had no effect on the difference between PC and arterial PCO2 or between EP and PC PCO2. Increasing benzolamide to 8 mg/kg increased PCO2 in the surface structures relative to arterial PCO2 by 3-5 mmHg (P less than 0.01). Metabolic acidosis did not alter the relationships between cortical and arterial PCO2. By contrast, respiratory alkalosis decreased cortical PCO2 relative to PaCO2 by over 50%. Nonetheless, EP PCO2 was still higher than LP or PC PCO2 (P less than 0.01). Thus, reducing HCO3(-) reabsorption does not obliterate the difference between EP and LP or PC PCO2 nor does it invariably reduce PCO2 in the surface structures of the kidney relative to arterial PCO2.