Morgan D A, DiBona G F, Mark A L
Department of Internal Medicine, Veterans Administration Medical Center, Iowa City, Iowa.
Hypertension. 1990 Apr;15(4):436-42. doi: 10.1161/01.hyp.15.4.436.
Previous studies using renal transplantation suggested that the genotype of a homograft kidney plays the primary role in determining chronic arterial pressure levels in Dahl salt-sensitive (DS) and salt-resistant (DR) rats, but this conclusion derived largely from observations during low NaCl diet. Recent studies indicate that extrarenal factors, including the sympathetic nervous system, play a critical role in the development of NaCl-induced hypertension in DS rats. To assess the contribution of extrarenal and renal factors in the development of NaCl-induced hypertension in Dahl rats, we performed renal transplantation in DS and DR rats. Both kidneys of the recipient were removed at the time of transplantation. Four groups of rats (n = 18-23 in each group) were fed a high NaCl (8.0%) diet for 2 weeks after renal transplantation. These included DRR, DRS, DSR, and DSS, where DR or DS indicates the recipient strain and the subscript indicates the homograft strain. Mean arterial pressure was measured from the femoral artery in conscious rats. On a high NaCl diet, mean arterial pressure was significantly lower (p less than 0.05) in DRR (103 +/- 2 mm Hg; mean +/- SEM) compared with DRS (145 +/- 5 mm Hg), DSR (151 +/- 7 mm Hg), and DSS (160 +/- 5 mm Hg). The finding that DR rats with a DS kidney (DRS) developed hypertension during high NaCl diet confirms the concept that the kidney plays an important hypertensinogenic role in the Dahl strain. The fact that DS rats with a DR kidney (DSR) also developed hypertension indicates that extrarenal factors also contribute significantly to NaCl-induced hypertension in DS rats.
以往利用肾移植进行的研究表明，同种异体移植肾的基因型在决定Dahl盐敏感（DS）大鼠和盐抵抗（DR）大鼠的慢性动脉血压水平中起主要作用，但这一结论在很大程度上源自低氯化钠饮食期间的观察结果。近期研究表明，包括交感神经系统在内的肾外因素在DS大鼠氯化钠诱导的高血压发展过程中起关键作用。为了评估肾外因素和肾因素在Dahl大鼠氯化钠诱导的高血压发展过程中的作用，我们对DS大鼠和DR大鼠进行了肾移植。在移植时将受体的双侧肾脏摘除。四组大鼠（每组n = 18 - 23）在肾移植后接受高氯化钠（8.0%）饮食2周。这些组包括DRR、DRS、DSR和DSS，其中DR或DS表示受体品系，下标表示同种异体移植品系。在清醒大鼠中通过股动脉测量平均动脉压。在高氯化钠饮食条件下，DRR组（103±2 mmHg；均值±标准误）的平均动脉压显著低于DRS组（145±5 mmHg）、DSR组（151±7 mmHg）和DSS组（160±5 mmHg）（p＜0.05）。具有DS肾的DR大鼠（DRS）在高氯化钠饮食期间出现高血压这一发现证实了肾脏在Dahl品系中起重要的致高血压作用这一概念。具有DR肾的DS大鼠（DSR）也出现高血压这一事实表明，肾外因素在DS大鼠氯化钠诱导的高血压中也起重要作用。
