Johnson D D, Tetzke T A, Cheung C Y
Department of Reproductive Medicine, University of California at San Diego, La Jolla 92093-0802, USA.
J Soc Gynecol Investig. 1994 Jan-Mar;1(1):14-8. doi: 10.1177/107155769400100104.
The present study quantified the abundance of atrial natriuretic factor (ANF) messenger RNA (mRNA) and determined the developmental pattern of ANF gene expression in the four cardiac chambers of the ovine fetus during the last two-thirds of gestation.
Twenty-one fetuses from 13 time-dated pregnant ewes at gestational ages of 60-145 days were used for this study. Total RNA from fetal atria and ventricles was extracted and ANF mRNA was analyzed by Northern blotting. The ANF mRNA signal was quantified by light densitometry. The abundance of ANF mRNA in the cardiac chambers across gestational ages was analyzed by linear regression analysis and one-way analysis of variance.
Atrial natriuretic factor mRNA was much more abundant in the atria than in the ventricles of all fetuses at each gestational age studied. Atrial ANF mRNA levels were lowest in the younger fetuses at 60 days and increased with advancing gestation. Ventricular ANF mRNA levels were highest in fetuses at 60 days and decreased to almost nondetectable levels near term. No difference in ANF mRNA abundance was noted between the right and left atria or the right and left ventricles at each gestational age.
A developmental pattern of ANF gene expression is demonstrated in the ovine fetal heart during the last two-thirds of gestation. This pattern shows that atrial ANF mRNA abundance increases while ventricular abundance decreases as the fetus matures. Expression of the ANF gene in the fetal period may be regulated developmentally or induced by cardiovascular changes in utero.
本研究对心房利钠因子（ANF）信使核糖核酸（mRNA）的丰度进行定量，并确定妊娠最后三分之二期间绵羊胎儿四个心腔中ANF基因表达的发育模式。
本研究使用了来自13只经定时妊娠的母羊的21只胎羊，胎羊的妊娠年龄为60 - 145天。提取胎儿心房和心室的总RNA，并通过Northern印迹法分析ANF mRNA。通过光密度测定法对ANF mRNA信号进行定量。通过线性回归分析和单因素方差分析分析不同妊娠年龄下心腔中ANF mRNA的丰度。
在每个研究的妊娠年龄，所有胎儿心房中的心房利钠因子mRNA比心室中的丰富得多。在60天的较年轻胎儿中，心房ANF mRNA水平最低，并随着妊娠进展而增加。在60天的胎儿中，心室ANF mRNA水平最高，在接近足月时降至几乎无法检测的水平。在每个妊娠年龄，左右心房或左右心室之间的ANF mRNA丰度没有差异。
在妊娠最后三分之二期间，绵羊胎儿心脏中显示出ANF基因表达的发育模式。这种模式表明，随着胎儿成熟，心房ANF mRNA丰度增加，而心室丰度降低。胎儿期ANF基因的表达可能受发育调控或由子宫内心血管变化诱导。
