Heimeier Rachel A, Davis Belinda J, Donald John A
School of Biological and Chemical Sciences, Deakin University, Geelong, Victoria 3217, Australia.
Comp Biochem Physiol A Mol Integr Physiol. 2002 Aug;132(4):893-903. doi: 10.1016/s1095-6433(02)00116-2.
This study investigated the mRNA expression of the atrial natriuretic peptide (ANP) system (peptide and receptors) during water deprivation in the spinifex hopping mouse, Notomys alexis, a native of central and western Australia that is well adapted to survive in arid environments. Initially, ANP, NPR-A and NPR-C cDNAs (partial for receptors) were cloned and sequenced, and were shown to have high homology with those of rat and mouse. Using a semi-quantitative multiplex PCR technique, the expression of cardiac ANP mRNA and renal ANP, NPR-A, and NPR-C mRNA was determined in 7- and 14-day water-deprived hopping mice, in parallel with control mice (access to water). The levels of ANP mRNA expression in the heart remained unchanged, but in the kidney ANP mRNA levels were increased in the 7-day water-deprived mice, and were significantly decreased in the 14-day water-deprived mice. NPR-A mRNA levels were significantly higher in 7-day water-deprived mice while no change for NPR-A mRNA expression was observed in 14-day water-deprived mice. No variation in NPR-C mRNA levels was observed. This study shows that water deprivation differentially affects the expression of the ANP system, and that renal ANP expression is more important than cardiac ANP in the physiological adjustment to water deprivation.
本研究调查了针鼹跳鼠（Notomys alexis）在缺水期间心房利钠肽（ANP）系统（肽和受体）的mRNA表达。针鼹跳鼠原产于澳大利亚中部和西部，非常适应在干旱环境中生存。首先，克隆并测序了ANP、NPR-A和NPR-C的cDNA（受体部分），并显示它们与大鼠和小鼠的cDNA具有高度同源性。使用半定量多重PCR技术，测定了7天和14天缺水的跳鼠以及对照小鼠（可获取水）心脏ANP mRNA和肾脏ANP、NPR-A和NPR-C mRNA的表达。心脏中ANP mRNA的表达水平保持不变，但在肾脏中，7天缺水的小鼠ANP mRNA水平升高，而14天缺水的小鼠则显著降低。7天缺水的小鼠NPR-A mRNA水平显著升高，而14天缺水的小鼠未观察到NPR-A mRNA表达变化。未观察到NPR-C mRNA水平的变化。本研究表明，缺水对ANP系统的表达有不同影响，并且在对缺水的生理调节中，肾脏ANP表达比心脏ANP更重要。
