Kirchhoff K, Forssmann W G
Niedersächsisches Institut für Peptid-Forschung (IPF), Feodor-Lynen - Strasse 31, D-30625 Hannover, Germany.
Pflugers Arch. 1995 Sep;430(5):739-44. doi: 10.1007/BF00386169.
Release of rat urodilatin (rURO) from isolated perfused rat kidneys and neonatal rat kidney cells could be demonstrated by a specific competitive radioimmunoassay (rURO-RIA) using [125I]rURO as the competitive antigen and an antiserum against the hypothetical rURO-N-terminus, Ala-Gly-Pro-Arg, as concluded from the amino acid sequence of the rat prohormone CDD/ANP-1-126. This antiserum did not react with synthetic rCDD/ANP-99-126, brain natriuretic peptide (BNP), C-type natriuretic peptide (CNP), or human URO (hURO). rURO could be demonstrated in the urine of the perfused rat kidney after an equilibration period of 20 min. After an initial slight decrease in the second 20 min, rURO production remained at almost the same level during the perfusion time of 100 min. A total of approximately 470 fmol.10 -1.g-1 kidney rURO was produced within 80 min. rURO was also produced by neonatal rat kidney cells kept in serum-free Dulbecco's modified Eagles medium. The production of rURO depended on the cultivation time of the cells. It increased up to 3 days reaching 239 +/- 7.5 fmol.h-1.g-1 protein, afterwards it decreased rapidly. The results obtained indicate that the rat kidney produces a peptide of the type A family of natriuretic peptides, which very likely represents the putative rURO.
利用[125I]大鼠尿舒张素（rURO）作为竞争抗原，以及根据大鼠前激素CDD/ANP-1-126的氨基酸序列推导出来的针对假定的rURO-N端Ala-Gly-Pro-Arg的抗血清，通过特异性竞争放射免疫分析（rURO-RIA）可证实rURO从离体灌注的大鼠肾脏和新生大鼠肾细胞中释放。该抗血清与合成的rCDD/ANP-99-126、脑钠肽（BNP）、C型钠肽（CNP）或人尿舒张素（hURO）均无反应。在平衡20分钟后，可在灌注大鼠肾脏的尿液中检测到rURO。在第二个20分钟内最初略有下降后，rURO的产生在100分钟的灌注时间内几乎保持在同一水平。在80分钟内总共产生了约470 fmol·10-1·g-1肾脏rURO。无血清的杜尔贝科改良伊格尔培养基中的新生大鼠肾细胞也能产生rURO。rURO的产生取决于细胞的培养时间。它在3天内增加，达到239±7.5 fmol·h-1·g-1蛋白质，之后迅速下降。所得结果表明，大鼠肾脏产生一种利钠肽A家族的肽，很可能就是假定的rURO。
