Biollaz J, Bidiville J, Diézi J, Waeber B, Nussberger J, Brunner-Ferber F, Gomez H J, Brunner H R
Department of Medicine, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
Kidney Int. 1987 Oct;32(4):537-46. doi: 10.1038/ki.1987.242.
The renal site of the natriuretic effect of human, atrial natriuretic peptide (hANP) was studied using clearance techniques in eight salt-loaded normal volunteers undergoing maximal water diuresis. Lithium was used as a marker of proximal sodium reabsorption. According to a two-way, single blind, crossover design, hANP (Met12-(3-28)-eicosahexapeptide, (2 micrograms/min) or its vehicle (Ve) were infused for two hours, followed by a two-hour recovery period. Blood pressure, heart rate and insulin clearance remained unchanged. During hANP infusion, the filtration fraction increased slightly from 19.6 to 24.3% (P less than 0.001), fractional water excretion rose transiently at the beginning of the infusion. Fractional excretion of sodium increased markedly from 2.2% to 7.4% (P less than 0.001) but remained unchanged with Ve. ANP increased fractional excretion of lithium slightly from 46 to 58% (P less than 0.01), while it remained stable at 47% during Ve. The distal tubular rejection fraction of sodium calculated from sodium and lithium clearances rose markedly from 4.7 to 13% (P less than 0.001) and returned to 6.2% at the end of the recovery period. Thus, under salt loading and water diuresis conditions, hANP infusion did not alter GFR, but reduced proximal reabsorption of sodium, and markedly enhanced the fraction of sodium escaping distal tubular reabsorption, suggesting that hANP-induced natriuresis is due, for an important part, to inhibition of sodium reabsorption in the distal nephron.
采用清除率技术，在8名处于最大水利尿状态的盐负荷正常志愿者中研究了人心房利钠肽（hANP）的利钠作用部位。锂用作近端钠重吸收的标志物。根据双盲、单向交叉设计，以2微克/分钟的速度输注hANP（Met12-(3-28)-二十碳六肽）或其溶媒（Ve），持续2小时，随后为2小时的恢复期。血压、心率和胰岛素清除率均未改变。在输注hANP期间，滤过分数从19.6%略有增加至24.3%（P<0.001），输注开始时水排泄分数短暂上升。钠排泄分数从2.2%显著增加至7.4%（P<0.001），但输注Ve时保持不变。ANP使锂排泄分数从46%略有增加至58%（P<0.01），而输注Ve期间则稳定在47%。根据钠和锂清除率计算的远端肾小管钠排泌分数从4.7%显著升至13%（P<0.0），恢复期结束时恢复至6.2%。因此，在盐负荷和水利尿条件下，输注hANP并未改变肾小球滤过率，但减少了近端钠重吸收，并显著增加了远端肾小管钠重吸收逃逸分数，提示hANP诱导的利钠作用在很大程度上是由于抑制了远端肾单位的钠重吸收。
