Keeler R, Feuchuk D, Wilson N
Department of Physiology, University of British Columbia, Vancouver, Canada.
Can J Physiol Pharmacol. 1987 Oct;65(10):2071-5. doi: 10.1139/y87-324.
Immunoreactive atrial natriuretic peptide (iANP) levels in plasma of edematous rats with an experimental nephrotic syndrome produced by the injection of puromycin aminonucleoside (PAN) were not different from those in untreated rats. To test the ability of nephrotic rats to secrete iANP in response to a volume stress, the rats were subjected to 20% expansion of their estimated blood volumes using blood from donor rats. PAN-treated rats had very small natriuretic and diuretic responses compared with untreated rats; however, there was no difference in the secretory response of iANP, which increased approximately threefold in each group. There were highly significant correlations between changes in plasma iANP and changes in right atrial pressure in both normal and nephrotic rats. Nephrotic rats that were infused with synthetic ANP showed only a very small natriuretic and diuretic response compared with normal rats, and no change in glomerular filtration rate. The hypotensive response was still present, however. Urine concentration in nephrotic rats was much lower than in controls and was not increased by exogenous arginine vasopressin. It is concluded that the absence of a normal natriuretic and diuretic response to hypervolemia in PAN-treated rats is not caused by a failure to secrete ANP but might be a result of an intrarenal defect that makes their kidneys unresponsive.
通过注射嘌呤霉素氨基核苷（PAN）产生实验性肾病综合征的水肿大鼠血浆中的免疫反应性心房利钠肽（iANP）水平与未处理大鼠的水平无差异。为了测试肾病大鼠对容量负荷应激分泌iANP的能力，使用供体大鼠的血液使大鼠的估计血容量增加20%。与未处理大鼠相比，PAN处理的大鼠利钠和利尿反应非常小；然而，iANP的分泌反应没有差异，每组中iANP均增加约三倍。正常大鼠和肾病大鼠血浆iANP变化与右心房压力变化之间均存在高度显著的相关性。与正常大鼠相比，输注合成ANP的肾病大鼠仅表现出非常小的利钠和利尿反应，肾小球滤过率无变化。然而，降压反应仍然存在。肾病大鼠的尿浓缩能力远低于对照组，且外源性精氨酸加压素不能使其增加。结论是，PAN处理的大鼠对血容量过多缺乏正常的利钠和利尿反应不是由于未能分泌ANP，而是可能由于肾内缺陷导致其肾脏无反应。
