Aalkjaer C, Mulvany M J, Nyborg N C
Br J Pharmacol. 1985 Oct;86(2):447-53. doi: 10.1111/j.1476-5381.1985.tb08914.x.
We have investigated the effect of a synthetic 'atrial natriuretic factor' (ANF) on induced tone in rat isolated renal arcuate arteries (lumen diameter ca. 250 microns), and compared this with the effects of synthetic ANF on resistance vessels of similar size taken from the mesenteric, femoral, cerebral and coronary vasculature. Synthetic ANF was found to cause relaxation of the renal vessels when these were sub-maximally activated with K+, noradrenaline or 5-hydroxytryptamine, but had no effect on the responses of the other vessels to these agonists. Synthetic ANF had a near maximal effect (65% relaxation) at 100 nM, with an IC50 of 7.9 nM. The relaxant effect of synthetic ANF on the renal vessels was fully maintained for at least 15 min. Hydralazine (100 microM) caused relaxation of renal vessels (47%) and coronary vessels (42%), but had no effect on the other vessel types. By contrast, sodium nitroprusside (1 microM) relaxed all vessel types. The relaxant action of synthetic ANF on the renal vessels was seen in the presence of ouabain (1 mM), propranolol (1 microM), phentolamine (1 microM), atropine (1 microM) and felodipine (1 nM). In t renal vessels, synthetic ANF had no effect on membrane potential, measured with intracellular electrodes, despite the simultaneously measured relaxation. Synthetic ANF had no effect on the efflux of 22Na+ in either renal or mesenteric vessels. The results demonstrate that synthetic ANF has a specific and prolonged relaxant effect on renal small arteries, and are consistent with this effect being mediated through specific receptors.
我们研究了合成的“心房利钠因子”（ANF）对大鼠离体肾弓状动脉（管腔直径约250微米）诱导张力的影响，并将其与合成ANF对取自肠系膜、股、脑和冠状血管系统的类似大小阻力血管的影响进行了比较。发现当肾血管用钾离子、去甲肾上腺素或5-羟色胺进行次最大激活时，合成ANF可使其舒张，但对其他血管对这些激动剂的反应没有影响。合成ANF在100 nM时具有接近最大的效应（65%舒张），IC50为7.9 nM。合成ANF对肾血管的舒张作用至少持续15分钟。肼屈嗪（100 microM）可使肾血管（47%）和冠状血管（42%）舒张，但对其他血管类型没有影响。相比之下，硝普钠（1 microM）可使所有血管类型舒张。在哇巴因（1 mM）、普萘洛尔（1 microM）、酚妥拉明（1 microM）、阿托品（1 microM）和非洛地平（1 nM）存在的情况下，仍可观察到合成ANF对肾血管的舒张作用。在肾血管中，尽管同时测量到舒张，但用细胞内电极测量时，合成ANF对膜电位没有影响。合成ANF对肾血管和肠系膜血管中的22Na+外流均无影响。结果表明，合成ANF对肾小动脉具有特异性且持久的舒张作用，并且这一作用与通过特异性受体介导相一致。
