Cuche J L, Ruget G, Selz F, Coquil J F, Guédon J
Arch Mal Coeur Vaiss. 1982 Jun;75 Spec No:63-6.
Renal handling of free catecholamines (dopamine, norepinephrine and epinephrine) was studied in 36 hydropenic anesthetized mongrel dogs in accordance with the clearance technique. There was no statistically significant correlation between plasma concentrations and either systemic (mean blood pressure, or cardiac output) or renal (clearance of PAH or glomerular filtration rate) hemodynamics. Net tubular transport (NTT) was calculated as the difference between filtered load and urinary excretion for any catecholamine. The mean NTTs of free catecholamines were as follows: --2,72 ng/min for dopamine, --3,18 for norepinephrine, and --1,36 for epinephrine, showing that they are mostly reabsorbed. However the use of averages is misleading inasmuch as tubular transport of free catecholamines is a heterogeneous phenomenon: a secretion appears to predominate when plasma concentrations are low and a reabsorption predominates when they are high. Whether such a heterogeneity is due to either a genetic heterogeneity in mongrel dogs, or an age-related difference is discussed.
采用清除率技术，对36只禁水麻醉的杂种犬的游离儿茶酚胺（多巴胺、去甲肾上腺素和肾上腺素）的肾脏处理情况进行了研究。血浆浓度与全身（平均血压或心输出量）或肾脏（对氨基马尿酸清除率或肾小球滤过率）血流动力学之间无统计学显著相关性。净肾小管转运（NTT）计算为任何儿茶酚胺的滤过负荷与尿排泄量之间的差值。游离儿茶酚胺的平均NTT如下：多巴胺为-2.72 ng/min，去甲肾上腺素为-3.18，肾上腺素为-1.36，表明它们大多被重吸收。然而，使用平均值具有误导性，因为游离儿茶酚胺的肾小管转运是一种异质性现象：当血浆浓度较低时，分泌似乎占主导地位，而当血浆浓度较高时，重吸收占主导地位。讨论了这种异质性是由于杂种犬的遗传异质性还是与年龄相关的差异。
