Rasmussen S N, Shalmi M, Hansen M, Christensen S
Institute of Medical Physiology B, University of Copenhagen, Denmark.
Ren Physiol Biochem. 1990 Nov-Dec;13(6):314-23. doi: 10.1159/000173376.
Renal plasma clearances (C) of 14C-tetraethylammonium (TEA) and p-aminohippurate (PAH) as estimates of arterial renal plasma flow (ARPF) were evaluated in anesthetized rats during control conditions and during intravenous glucose infusion. Venous renal blood flow was measured directly by means of a servo-controlled pump, keeping the renal venous pressure constant. Arteriovenous extraction fractions (E = 1 - P(renal venous)/P(renal arterial)) for PAH averaged 88.3 +/- (SE) 0.8% in control rats and 82.0 +/- 0.9% in glucose-infused rats (p less than 0.001); E(TEA) averaged 92.0 +/- 0.6 and 90.1 +/- 0.6%, respectively (p less than 0.05). Under both experimental conditions, (C/E)PAH did not differ significantly from ARPF, while (C/E)TEA underestimated ARPF; the rate of extraction of TEA exceeded the rate of excretion by 15-20%, probably due to accumulation of TEA in renal tissue. It is concluded that, when corrected for E, C(PAH) is in general a more accurate estimate for ARPF than C(TEA). However, under conditions involving changes in plasma glucose levels C(TEA) may provide a better estimate of the effective renal plasma flow than C(PAH).
在麻醉大鼠的对照条件下以及静脉输注葡萄糖期间，评估了用14C - 四乙铵（TEA）和对氨基马尿酸（PAH）的肾血浆清除率（C）来估算肾动脉血浆流量（ARPF）的情况。通过伺服控制泵直接测量肾静脉血流量，保持肾静脉压力恒定。对照大鼠中PAH的动静脉提取分数（E = 1 - P（肾静脉）/P（肾动脉））平均为88.3±（标准误）0.8%，葡萄糖输注大鼠中为82.0±0.9%（p < 0.001）；TEA的E分别平均为92.0±0.6%和90.1±0.6%（p < 0.05）。在两种实验条件下，（C/E）PAH与ARPF无显著差异，而（C/E）TEA低估了ARPF；TEA的提取率超过排泄率15 - 20%，这可能是由于TEA在肾组织中的蓄积。结论是，校正E后，C（PAH）总体上比C（TEA）更准确地估算ARPF。然而，在血浆葡萄糖水平发生变化的情况下，C（TEA）可能比C（PAH）能更好地估算有效肾血浆流量。
