Ogihara T, Shima J, Hara H, Tabuchi Y, Hashizume K, Kumahara Y, Kangawa K, Matsuo H
Jpn Heart J. 1987 Jan;28(1):41-51. doi: 10.1536/ihj.28.41.
The physiological mechanism regulating secretion of human atrial natriuretic polypeptide (hANP) was examined by measuring plasma hANP by a specific radioimmunoassay during head-out total body water immersion (WI) and saline infusion in normal men. Seven healthy men were immersed in water for 1 hour, 6 normal men and women were given an infusion of 1 liter of normal saline over 1 hour and 8 normal men were given a similar infusion over 2 hours. During WI, the urinary volume (UV) and urinary Na excretion (UNaV) increased significantly, and the plasma hANP level increased significantly from 246 +/- 12 (mean +/- SE) pg/ml to 392 +/- 32 pg/ml after 35 +/- 5 min, but returned to the basal level after 90 min. The increase in hANP level was correlated with an increased UNaV between 30 to 60 min during WI. The plasma norepinephrine, renin activity, aldosterone and cortisol levels also decreased during WI. Saline infusion caused variable increases in the hANP level: the mean peak values of hANP and times of the peaks from the start of saline infusion were respectively 305 +/- 30 pg/ml after 30 +/- 3 min of infusion at a rate of 1L/1 hr and 285 +/- 25 pg/ml after 69 +/- 15 min of infusion at a rate of 1L/2 hrs. The time of the peak of plasma hANP during infusion at 1L/2 hrs was significantly longer than the peaks for WI or an infusion of saline at 1L/1 hr. Moreover, the peak hANP level was significantly smaller during either condition of saline infusion than during water immersion. These results indicate that i) acute central hypervolemia caused by WI increases hANP secretion, and this increase may participate in natriuresis during WI, and ii) saline infusion causes an increase in plasma hANP of variable magnitude, the increase being more rapid for a more rapid infusion of saline. This suggests that hANP is released into the circulation by acute volume expansion and plays a physiologically important role in maintaining blood volume homeostasis in man.
通过在正常男性进行头低位全身水浸（WI）和生理盐水输注期间，使用特异性放射免疫测定法测量血浆人心房利钠多肽（hANP），研究了调节hANP分泌的生理机制。7名健康男性在水中浸泡1小时，6名正常男性和女性在1小时内输注1升生理盐水，8名正常男性在2小时内进行类似输注。在WI期间，尿量（UV）和尿钠排泄量（UNaV）显著增加，血浆hANP水平在35±5分钟后从246±12（平均值±标准误）pg/ml显著增加至392±32 pg/ml，但在90分钟后恢复至基础水平。WI期间30至60分钟内hANP水平的增加与UNaV的增加相关。WI期间血浆去甲肾上腺素、肾素活性、醛固酮和皮质醇水平也降低。生理盐水输注导致hANP水平有不同程度的升高：以1L/1小时的速率输注30±3分钟后，hANP的平均峰值为305±30 pg/ml；以1L/2小时的速率输注69±15分钟后，hANP的平均峰值为285±25 pg/ml。以1L/2小时的速率输注期间血浆hANP达到峰值的时间明显长于WI或以1L/1小时的速率输注生理盐水时的峰值时间。此外，在两种生理盐水输注条件下，hANP的峰值水平均显著低于水浸期间。这些结果表明：i）WI引起的急性中枢性血容量过多会增加hANP分泌，这种增加可能参与WI期间的利钠作用；ii）生理盐水输注会导致血浆hANP有不同程度的升高，输注速度越快，升高越迅速。这表明hANP通过急性容量扩张释放到循环中，在维持人体血容量稳态中发挥重要的生理作用。
