Lenz T, James G D, Laragh J H, Sealey J E
Cardiovascular Center, New York Hospital, Cornell University Medical College, New York 10021.
Am J Physiol. 1991 Jun;260(6 Pt 1):E876-82. doi: 10.1152/ajpendo.1991.260.6.E876.
We examined whether renin (prorenin plus renin) is secreted from the human placenta into the maternal or fetal circulation and compared the secretion rate to that of human chorionic gonadotropin (hCG), progesterone, and estradiol. While estradiol and progesterone passed into both circulations, renin (mostly prorenin) and hCG were secreted predominantly into the maternal circulation. To examine if prorenin passed from the maternal to the fetal circulation and vice versa, we perfused both circuits separately with exogenous recombinant human prorenin. No prorenin passed from maternal to fetal circulations, but a small amount (less than 10%) slowly passed from fetal to maternal, beginning 15 min after the addition of prorenin. Exogenous prorenin was not converted to renin in either circulation. Perfusate total renin had close to 10% active renin, whereas that of tissue extracts was closer to 50%. In conclusion, the results are consistent with some tissue activation of prorenin, either in vitro or in vivo, but no activation in the maternal or fetal circulations. The human placenta may secrete prorenin into the maternal but not into the fetal circulation. The possibility that the placenta may secrete a small amount of active renin into the maternal circulation was not ruled out.
我们研究了肾素（前肾素加肾素）是否从人胎盘分泌至母体或胎儿循环中，并将其分泌速率与人类绒毛膜促性腺激素（hCG）、孕酮和雌二醇的分泌速率进行了比较。虽然雌二醇和孕酮可进入两种循环，但肾素（主要是前肾素）和hCG主要分泌至母体循环中。为了研究前肾素是否从母体循环进入胎儿循环，反之亦然，我们分别用外源性重组人前肾素灌注两个循环。没有前肾素从母体循环进入胎儿循环，但加入前肾素15分钟后，少量（不到10%）前肾素缓慢地从胎儿循环进入母体循环。外源性前肾素在任一循环中均未转化为肾素。灌注液中的总肾素含有近10%的活性肾素，而组织提取物中的活性肾素含量更接近50%。总之，结果表明，前肾素在体外或体内可能有一些组织激活，但在母体或胎儿循环中没有激活。人胎盘可能将前肾素分泌至母体循环而非胎儿循环中。并未排除胎盘可能向母体循环中分泌少量活性肾素的可能性。
