Hamid Q, Wharton J, Terenghi G, Hassall C J, Aimi J, Taylor K M, Nakazato H, Dixon J E, Burnstock G, Polak J M
Department of Histochemistry, Royal Postgraduate Medical School, London, United Kingdom.
Proc Natl Acad Sci U S A. 1987 Oct;84(19):6760-4. doi: 10.1073/pnas.84.19.6760.
The localization of mRNA encoding preproatrial natriuretic peptide was investigated in tissue sections and cultures of rat heart and in sections of human right atrial appendage using the technique of in situ hybridization with 32P- and 35S-labeled RNA probes. Rat atrial natriuretic peptide (ANP) transcripts were demonstrated in numerous atrial myocytes and, to a lesser extent, in ventricular myocytes in both tissue sections and newborn rat heart cultures. These findings are consistent with those obtained by RNA blot analysis of rat heart total RNA, indicating that a single prepro-ANP transcript of approximately 900 nucleotides was present in the ventricles as well as the atria. Using a 35S-labeled RNA probe for human ANP mRNA, ANP transcripts were also localized to the majority of myocytes in the human right atrial appendage. Only background levels of autoradiographic labeling were obtained when RNA probes identical to the coding sequence of rat or human ANP mRNA were used. A close correlation was found between the distribution of ANP immunoreactivity and prepro-ANP mRNA in these preparations. These results provide unequivocal evidence for the expression of the ANP gene in the rat ventricles, as well as the atria, because myocytes in these tissues have been established as the sites of both ANP localization and precursor biosynthesis. The combined use of cardiac cultures and in situ hybridization may be of value in future studies investigating the regulation of ANP synthesis in cardiac myocytes.
采用32P和35S标记的RNA探针原位杂交技术，对大鼠心脏组织切片和培养物以及人右心耳切片中编码前心钠素原的mRNA进行了定位研究。在组织切片和新生大鼠心脏培养物中，在大量心房肌细胞中均检测到大鼠心钠素（ANP）转录本，在心室肌细胞中也有较少程度的检测到。这些发现与通过大鼠心脏总RNA的RNA印迹分析获得的结果一致，表明在心室和心房中均存在约900个核苷酸的单一前心钠素原转录本。使用针对人ANP mRNA的35S标记RNA探针，ANP转录本也定位于人右心耳的大多数肌细胞中。当使用与大鼠或人ANP mRNA编码序列相同的RNA探针时，仅获得了放射自显影标记的背景水平。在这些制剂中发现ANP免疫反应性分布与前心钠素原mRNA之间存在密切相关性。这些结果为ANP基因在大鼠心室以及心房中的表达提供了明确的证据，因为这些组织中的肌细胞已被确定为ANP定位和前体生物合成的部位。心脏培养物和原位杂交的联合使用在未来研究心肌细胞中ANP合成的调节方面可能具有价值。
