Lear W, Boer P H
University of Ottawa Heart Institute Research Centre, Ontario, Canada.
Cardiovasc Res. 1995 May;29(5):676-81.
The aim was to compare activities of the type A and type B natriuretic factor genes during development of cardiac hypertrophy by use of a non-radioactive method designed for assessment of stable atrial and brain natriuretic factor (ANF, BNF) transcript levels in biopsy sized tissue samples.
At 1 and 7 days after aortocaval shunt or sham surgery in rats, quantitative reverse transcriptase mediated polymerase chain reaction (Q-RT-PCR) was used to determine mRNA levels in cardiac tissues. Phosphoglycerate kinase-1 (PGK-1) mRNA levels served as an external standard for Q-RT-CR.
The shunt increased left ventricular end diastolic pressure at days 1 and 7, and cardiac weight was increased by day 7. By day 1, left ventricular BNF mRNA levels were twice those of controls, whereas ANF mRNA levels were not changed. By day 7, left ventricular BNF mRNA levels were increased 15-fold, and those for ANF were increased fivefold; the BNF mRNAs were also increased in right atria and right ventricle, about fivefold in both cases.
Both natriuretic factor genes were activated by cardiac volume overload, and the increase in the level of left ventricular BNF transcripts-observed for the first time-was in fact more rapid and exceeded that of ANF. The Q-RT-PCR assay will be of value to investigate the response to increased work load of cardiac muscle in vivo.
旨在通过一种非放射性方法比较心脏肥大发展过程中 A 型和 B 型利钠因子基因的活性，该方法用于评估活检大小的组织样本中稳定的心房利钠因子和脑利钠因子（ANF，BNF）转录水平。
在大鼠进行主动脉腔静脉分流术或假手术后 1 天和 7 天，使用定量逆转录酶介导的聚合酶链反应（Q-RT-PCR）来测定心脏组织中的 mRNA 水平。磷酸甘油酸激酶-1（PGK-1）mRNA 水平用作 Q-RT-CR 的外部标准。
分流术在第 1 天和第 7 天增加了左心室舒张末期压力，到第 7 天心脏重量增加。到第 1 天，左心室 BNF mRNA 水平是对照组的两倍，而 ANF mRNA 水平未改变。到第 7 天，左心室 BNF mRNA 水平增加了 15 倍，ANF 增加了 5 倍；右心房和右心室中的 BNF mRNA 也增加，两者均约为 5 倍。
两种利钠因子基因均因心脏容量超负荷而被激活，首次观察到的左心室 BNF 转录本水平的增加实际上更快且超过了 ANF。Q-RT-PCR 测定法对于研究体内心肌对增加的工作负荷的反应将具有价值。
