Persson P B, Baumann J E, Ehmke H, Hackenthal E, Kirchheim H R, Nafz B
I. Physiologisches Institut, Universität Heidelberg, Germany.
Am J Physiol. 1993 Jun;264(6 Pt 2):F943-7. doi: 10.1152/ajprenal.1993.264.6.F943.
The effect of blocking the formation of endothelium-derived relaxing factor/nitric oxide (EDNO) on pressure-dependent renin release (RR) was studied in six conscious foxhounds with chronically implanted catheters in the abdominal aorta and the renal vein. Renal blood flow (RBF) was measured with an ultrasonic transit-time flowmeter. RR was determined by multiplying the renal venous-arterial plasma renin activity difference with renal plasma flow. Renal artery pressure (RAP) was reduced in steps by a pneumatic occluder placed around the suprarenal abdominal aorta. A dose of 1,000 mg NG-nitro-L-arginine methyl ester (L-NAME) was given as a bolus to inhibit EDNO formation. In response to L-NAME, RAP increased (98 +/- 3 vs. 128 +/- 3 mmHg; P < 0.05), heart rate decreased (88 +/- 7 vs. 51 +/- 5 beats/min; P < 0.05), RBF decreased (280 +/- 19 vs. 185 +/- 24 ml/min; P < 0.05), and RR decreased (62 +/- 11 vs. 28 +/- 7 U; P < 0.05), whereas glomerular filtration rate changed little (38 +/- 3 vs. 35 +/- 4 ml/min; not significant). Below roughly 90 mmHg, RR was considerably attenuated by L-NAME as RAP was reduced in steps. At the lowest RAP (50 mmHg) RR was 1,946 +/- 406 U during control vs. 697 +/- 179 U after L-NAME (P < 0.05). Thus L-NAME inhibited pressure-dependent RR. This was especially pronounced in the low-pressure range.
在六只经腹主动脉和肾静脉长期植入导管的清醒猎狐犬中，研究了阻断内皮源性舒张因子/一氧化氮（EDNO）形成对压力依赖性肾素释放（RR）的影响。用超声渡越时间流量计测量肾血流量（RBF）。RR通过肾静脉-动脉血浆肾素活性差异与肾血浆流量相乘来确定。通过置于肾上腺上方腹主动脉周围的气动闭塞器逐步降低肾动脉压（RAP）。静脉推注1000 mg NG-硝基-L-精氨酸甲酯（L-NAME）以抑制EDNO形成。给予L-NAME后，RAP升高（98±3 vs. 128±3 mmHg；P<0.05），心率降低（88±7 vs. 51±5次/分钟；P<0.05），RBF降低（280±19 vs. 185±24 ml/分钟；P<0.05），RR降低（62±11 vs. 28±7 U；P<0.05），而肾小球滤过率变化不大（38±3 vs. 35±4 ml/分钟；无统计学意义）。在大约90 mmHg以下，随着RAP逐步降低，L-NAME使RR明显减弱。在最低RAP（50 mmHg）时，对照期间RR为1946±406 U，给予L-NAME后为697±179 U（P<0.05）。因此，L-NAME抑制压力依赖性RR。这在低压范围内尤为明显。
