Yono Makoto, Latifpour Jamshid, Takahashi Wataru, Pouresmail Mehdi, Afiatpour Parviz, Weiss Robert M
Section of Urology, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
J Recept Signal Transduct Res. 2004 Feb;24(1-2):53-66. doi: 10.1081/rrs-120034106.
As age-related changes occur in the properties of the endothelin (ET) receptor system in several mammalian tissues, and as there are significant amounts of functional ET receptors in the vas deferens, we investigated the age-related changes in the ET receptor system at the protein and mRNA levels in the rat vas deferens. The ET system was investigated in the vasa deferentia of 3 weeks, 3 months and 22 months old rats. ET receptors were characterized and quantified at the protein level by radioligand receptor binding, and gene transcript levels of ET-1, ET-3, ET converting enzyme-1 (ECE-1), and ET(A) and ET(B) receptor subtypes were quantified by real-time reverse transcription polymerase chain reaction (RT-PCR). The results of radioligand receptor binding assays demonstrate that there is a higher density of total ET receptors in the vas deferens of 3 weeks old rats than in 3 months and 22 months old rats, and that the predominant ET receptor is of the ET(A) subtype in all three ages. Real-time RT-PCR data show that the predominant mRNA expression of ETs and their receptors in all age groups studied are ET-1 and the ET(A) receptor subtype, respectively. Furthermore, ET-1, ET-3, ECE-1, and ET(A) and ET(B) receptor subtype mRNAs are expressed at higher levels in the 3 weeks old rats as compared with the other two age groups. These results demonstrate the presence of age-related changes in the properties of the ET receptor system at both protein and mRNA levels in the rat vas deferens.
随着与年龄相关的变化出现在多种哺乳动物组织中的内皮素（ET）受体系统特性中，并且由于输精管中存在大量功能性ET受体，我们研究了大鼠输精管中ET受体系统在蛋白质和mRNA水平上与年龄相关的变化。在3周龄、3月龄和22月龄大鼠的输精管中研究ET系统。通过放射性配体受体结合在蛋白质水平上对ET受体进行表征和定量，并通过实时逆转录聚合酶链反应（RT-PCR）对ET-1、ET-3、ET转换酶-1（ECE-1）以及ET（A）和ET（B）受体亚型的基因转录水平进行定量。放射性配体受体结合试验的结果表明，3周龄大鼠输精管中总ET受体的密度高于3月龄和22月龄大鼠，并且在所有三个年龄段中，主要的ET受体是ET（A）亚型。实时RT-PCR数据显示，在所有研究的年龄组中，ET及其受体的主要mRNA表达分别是ET-1和ET（A）受体亚型。此外，与其他两个年龄组相比，ET-1、ET-3、ECE-1以及ET（A）和ET（B）受体亚型的mRNA在3周龄大鼠中的表达水平更高。这些结果表明，大鼠输精管中ET受体系统的特性在蛋白质和mRNA水平上均存在与年龄相关的变化。
