Itoh S, Abe K, Nushiro N, Omata K, Yasujima M, Yoshinaga K
Second Department of Internal Medicine, Tohoku University School of Medicine, Sendai, Japan.
Kidney Int. 1987 Oct;32(4):493-7. doi: 10.1038/ki.1987.237.
This study was designed to examine the effect of alpha-human atrial natriuretic polypeptide (alpha-hANP) on renin release in the absence of tubules, glomeruli and macula densa. Rabbit afferent arterioles were microdissected and incubated for two consecutive, 20 minute periods. Hourly renin release rate from a single arteriole was calculated. Basal renin release rate was 0.97 +/- 0.13 ng AI.hr-1.Af-1/hr (X +/- SEM, N = 18) and remained stable throughout the incubations. When afferent arterioles were exposed to alpha-hANP (0.01, 0.1 or 1 microM), renin release rate did not change significantly. Isoproterenol (5 microM) increased renin release rate from 0.92 +/- 0.28 to 1.50 +/- 0.46 ng AI.hr-1.Af-1/hr (N = 7, P less than 0.01). After pretreatment of afferent arterioles with alpha-hANP (1 microM), isoproterenol still increased renin release rate from 0.98 +/- 0.24 to 1.64 +/- 0.37 ng AI.hr-1.Af-1/hr (N = 7, P less than 0.01). The increases in renin release rate induced by isoproterenol were not different between the two groups. Pretreatment of rabbits with furosemide for two days before experiments resulted in greater basal renin release rates from microdissected afferent arterioles (1.70 +/- 0.35 ng AI.hr-1.Af-1/hr, N = 14). However, exposure to alpha-hANP (1 microM) did not alter this elevated renin release rate. It is concluded that atrial natriuretic factor may not have a direct action on juxtaglomerular cells.
本研究旨在检测α-人心房利钠多肽（α-hANP）在无肾小管、肾小球和致密斑情况下对肾素释放的影响。对兔传入小动脉进行显微解剖，并连续孵育两个20分钟时段。计算单个小动脉每小时的肾素释放率。基础肾素释放率为0.97±0.13 ng AI·hr⁻¹·Af⁻¹/hr（X±SEM，N = 18），且在整个孵育过程中保持稳定。当传入小动脉暴露于α-hANP（0.01、0.1或1 μM）时，肾素释放率无显著变化。异丙肾上腺素（5 μM）使肾素释放率从0.92±0.28增加至1.50±0.46 ng AI·hr⁻¹·Af⁻¹/hr（N = 7，P<0.01）。用α-hANP（1 μM）预处理传入小动脉后，异丙肾上腺素仍使肾素释放率从0.98±0.24增加至1.64±0.37 ng AI·hr⁻¹·Af⁻¹/hr（N = 7，P<0.01）。两组中异丙肾上腺素诱导的肾素释放率增加无差异。实验前用速尿预处理兔两天，导致显微解剖的传入小动脉基础肾素释放率更高（1.70±0.35 ng AI·hr⁻¹·Af⁻¹/hr，N = 14）。然而，暴露于α-hANP（1 μM）并未改变这种升高的肾素释放率。结论是心房利钠因子可能对球旁细胞没有直接作用。
