Frei U, Schindler R, Matthies C, Koch K M
Department of Nephrology, Medizinische Hochschule Hannover, FRG.
J Pharmacol Exp Ther. 1992 Dec;263(3):938-42.
Glomerular hemodynamics of the clipped kidney in two kidney-one clip Goldblatt-hypertensive rats were studied by micropuncture techniques after administration of either captopril (20 mg/kg of b.wt./day p.o.) or diltiazem (3 mg/kg of b.wt./hr i.v.). Both drugs decreased mean arterial and poststenotic renal arterial pressure to comparable levels. Total kidney glomerular filtration rate was not significantly different in the three groups (0.78 +/- 0.09 in hypertensive controls, 0.62 +/- 0.11 after captopril and 0.74 +/- 0.07 ml/min/g of kidney weight after diltiazem). Glomerular capillary pressure fell significantly in both treated groups but was lower in captopril-treated animals (60 +/- 2 in hypertensive controls, 45 +/- 2 after captopril and 53 +/- 1 mm Hg after diltiazem, both P < .05 vs. hypertensive controls). Afferent arteriolar resistance was lowered in both treatment groups to the same extent, whereas only captopril decreased efferent arteriolar resistance. Single nephron filtration rate of cortical nephrons was not altered significantly by captopril due to a 96% increase in the ultrafiltration coefficient and a 58% rise in glomerular plasma flow, whereas diltiazem increased ultrafiltration coefficient by 62% but did not affect glomerular plasma flow. These studies indicate that, despite of decreased effective filtration pressure, glomerular filtration rate is well preserved after converting enzyme inhibition. Captopril and diltiazem have different effects on glomerular hemodynamics within the stenosed kidney.
采用微穿刺技术，对两肾一夹型Goldblatt高血压大鼠夹闭侧肾脏的肾小球血流动力学进行了研究，分别给予卡托普利（20mg/kg体重/天，口服）或地尔硫䓬（3mg/kg体重/小时，静脉注射）。两种药物均使平均动脉压和肾动脉狭窄后压力降至相当水平。三组的总肾肾小球滤过率无显著差异（高血压对照组为0.78±0.09，卡托普利治疗后为0.62±0.11，地尔硫䓬治疗后为0.74±0.07ml/min/g肾重）。两个治疗组的肾小球毛细血管压力均显著下降，但卡托普利治疗的动物更低（高血压对照组为60±2，卡托普利治疗后为45±2，地尔硫䓬治疗后为53±1mmHg，两者与高血压对照组相比P<0.05）。两个治疗组的入球小动脉阻力均降低到相同程度，而只有卡托普利降低了出球小动脉阻力。由于超滤系数增加96%和肾小球血浆流量增加58%，卡托普利对皮质肾单位的单肾单位滤过率无显著影响，而地尔硫䓬使超滤系数增加62%，但不影响肾小球血浆流量。这些研究表明，尽管有效滤过压降低，但转换酶抑制后肾小球滤过率仍得到良好维持。卡托普利和地尔硫䓬对狭窄肾脏内的肾小球血流动力学有不同影响。
