Selective preglomerular constriction to nerve stimulation in rat hydronephrotic kidneys.
Selective preglomerular constriction to nerve stimulation in rat hydronephrotic kidneys.
复制标题
大鼠肾积水肾脏神经刺激的选择性肾小球前收缩。
DOI：
10.1152/ajprenal.1992.262.3.f348
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发表时间：
1992
期刊：
影响因子：
--
通讯作者：
Porter,JP
中科院分区：
文献类型：
--
作者：
Fleming,JT;Zhang,C;Chen,J;Porter,JP
本研究的目的是通过直接观察完整的微循环，量化肾小球前微血管和肾小球后微血管在肾神经活动短暂增加时的收缩反应。为了验证大鼠肾积水模型在这方面的应用，通过量化静脉给药去甲肾上腺素、电刺激下丘脑后部和直接刺激肾神经引起的全肾血流速度变化，评估肾积水肾脏和正常肾脏的血管反应性对肾上腺素和神经的刺激。肾积水和非肾积水对去甲肾上腺素和下丘脑后部刺激的反应相当；然而，与正常肾脏相比，肾积水肾脏对直接肾神经刺激的反应较差。在微循环实验中，刺激内脏神经（2-8 Hz）诱导小叶间动脉和传入小动脉的频率依赖性收缩。在8 hz刺激下，肾小球前血管直径下降42-53%，而传出小动脉直径无明显变化。因此，肾小球前血管的收缩在很大程度上介导了肾交感神经活动增加所引起的肾血流动力学变化。
The purpose of this study was to quantitate the constrictor responses of pre- vs. postglomerular microvessels during brief increases in renal nerve activity by directly observing the intact microcirculation. To validate the use of the rat hydronephrotic kidney model for this purpose, the vascular reactivity of hydronephrotic kidneys, and normal kidneys was assessed to adrenergic and neural stimulation by quantitating whole kidney blood flow velocity changes elicited by intravenous administration of norepinephrine, electrical stimulation of the posterior hypothalamus, and direct renal nerve stimulation. Hydronephrotic and nonhydronephrotic kidneys responded comparably to norepinephrine and posterior hypothalamic stimulation; however, the hydronephrotic kidneys were less responsive than normal kidneys to direct renal nerve stimulation. In the microcirculatory experiments, stimulation of the splanchnic nerve (2-8 Hz) induced a frequency-dependent constriction of interlobular arteries and afferent arterioles. Preglomerular vessel diameters decreased by 42-53% during the 8-Hz stimulation, whereas the efferent arteriolar diameters did not significantly change. Thus, constriction of preglomerular vessels mediates, in large part, the changes in renal hemodynamics evoked by increases in renal sympathetic nerve activity.