经血管转染iNOS基因对大鼠的降血压作用

The Decreasing Blood Pressure Effect by Transfecting iNOS Gene via Vein in Rat

目的研究经大鼠尾静脉转染ｉＮＯＳ基因对大鼠血压的影响。方法从尾静脉注射经磷酸钙包裹的载有人类全长ｉＮＯＳｃＤＮＡ的表达质粒进入大鼠体内后，检测大鼠血压的改变及培养大鼠腹腔巨噬细胞上清液中ＮＯ的含量。结果（１）大鼠的血压从转染前的１８４．４７±７．８５ｍｍＨｇ，１６２．２３±１４．１３ｍｍＨｇ，于转染后第２天分别下降为１４５．２４±１３．４３ｍｍＨｇ（Ｐ＜０．０５，ｎ＝５）及１２８．９０±１５．０６ｍｍＨｇ（Ｐ＜０．０５，ｎ＝５），血压降低能维持６天以上；（２）转染ｉＮＯＳ基因使培养大鼠腹腔巨噬细胞上清液中ＮＯ水平由０．１２２±０．０１４ＯＤ值上升为０．２５４±０．０３１ＯＤ值３３（Ｐ＜０．０１，ｎ＝５，转染后第３天）及由０．１２５±０．０２１ＯＤ值上升为０．２０９±０．０１９ＯＤ值（Ｐ＜０．０１，ｎ＝５，转染后第６天）。结论静脉注射经磷酸钙包裹的ｉＮＯＳ基因进入大鼠体内，能成功地转染巨噬细胞，也可能转染其他具有吞噬功能的细胞，并表达其产物，使ＮＯ生成持续增加，导致血管舒张，血压降低，并在一段时间内维持较低水平。

Aim\ To research the change of blood pressure which was caused by transfecting iNOS gene via vein in rat.\ Methods\ After injecting the expression plasmid which carried the full length human iNOS cDNA and was packed by Ca 3(PO 4) 2 into rat via tail vein, we investigated the change of their blood pressure and the NO concentration in supernatant of culture rat peritoneal macrophage.\ Results\ (1)The blood pressure of rat were 18447± 785 mmHg, 16223±1413 mmHg before gene transfection, they reduced to 14524±1343 mmHg(P<005, n=5) and 12890±1506 mmHg(P<005, n=5) respectively in the 2nd day after transfection.\ The reduction can maintain at least 6 days.\ (2)Gene transfection can make the NO concentration in supernatant of culture rat peritoneal macrophage increased from 0122±0014 OD value to 0254±0031 OD value(P<001, n=5, the 3rd day after transfection) as well as from 0125±0021 OD value to 0209±0019 OD value(P<001, n=5, the 6th day after transfection).\ Conclusion\ Injecting the expression plasmid which carried the full length human iNOS cDNA and was packed by Ca 3(PO 4) 2 into rat via vein could transfect the macrophage successfully, or may transfect other kinds of englobe cells also.\ Moreover, the transfected gene can express its gene product which can make NO increase in vivo persistently.\ The increased NO can lead to blood vessel dilatation and blood pressure decrease for a period of time.\ This experiment might provides a new and rather easy method to the research of gene transfection in cardiovascular system in vivo.