Qing G, Garcia R
Laboratory of Experimental Hypertension and Vasoactive Peptides, Clinical Research Institute of Montreal, Quebec, Canada.
Cardiovasc Res. 1993 Mar;27(3):464-70. doi: 10.1093/cvr/27.3.464.
The aims were (1) to characterise plasma and tissue atrial natriuretic factor (ANF) levels, haemodynamic variables, and renal function at different stages of moderate chronic high output heart failure in the rat; and (2) to assess the contribution of the atria and ventricles to plasma ANF levels.
Plasma and tissue ANF levels, haemodynamics, and renal function were evaluated at 1, 2, 4, 8, and 16 weeks after the development of aorto-caval shunts. Sham operated animals served as controls at identical time points. Male Sprague-Dawley rats weighing 225-275 g were used in all experiments.
Mean arterial blood pressure was lower and right atrial pressure was higher in the aorto-caval shunt groups than in sham operated controls at all time periods. Left ventricular end diastolic pressure was increased significantly in aorto-caval shunt rats at 1, 2, and 4 weeks when compared with their control counterparts. Plasma COOH terminal and NH2 terminal ANF concentrations were increased significantly in aorto-caval shunt animals. Plasma ANF was positively correlated with right atrial pressure and left ventricular end diastolic pressure in aorto-caval shunt rats but not in sham operated controls. Aorto-caval shunt animals also developed marked cardiac hypertrophy with decreased atrial ANF concentration, but not content, and increased ventricular ANF concentration and content. Despite high plasma ANF concentrations, aorto-caval shunt rats had a lower packed cell volume at all observed periods and reduced urinary sodium excretion and urinary volume at 1 and 2 weeks, with trends to a reduction at 4, 8, and 16 weeks. Body weight was higher in aorto-caval shunt animals at 16 weeks than in sham operated controls.
(1) Chronically increased cardiac filling pressure stimulated not only ANF release but also ANF synthesis in each cardiac chamber, which in turn contributed to raised plasma ANF concentrations in aorto-caval shunt rats; (2) an attenuated renal response to endogenous ANF and sodium and water retention were apparent in A-C shunt rats. Activation of neurohormonal vasoconstrictor systems and gradually decreased plasma ANF concentrations may contribute to sodium and water retention at different stages of this experimental model of heart failure.
（1）对大鼠中度慢性高输出量心力衰竭不同阶段的血浆和组织心房利钠因子（ANF）水平、血流动力学变量及肾功能进行特征描述；（2）评估心房和心室对血浆ANF水平的作用。
在建立主动脉-腔静脉分流术后1、2、4、8和16周，评估血浆和组织ANF水平、血流动力学及肾功能。假手术动物在相同时间点作为对照。所有实验均使用体重225 - 275 g的雄性Sprague-Dawley大鼠。
在所有时间段，主动脉-腔静脉分流组的平均动脉血压低于假手术对照组，右心房压力高于假手术对照组。与对照大鼠相比，主动脉-腔静脉分流大鼠在1、2和4周时左心室舒张末期压力显著升高。主动脉-腔静脉分流动物的血浆COOH末端和NH2末端ANF浓度显著升高。在主动脉-腔静脉分流大鼠中，血浆ANF与右心房压力和左心室舒张末期压力呈正相关，而在假手术对照组中无此相关性。主动脉-腔静脉分流动物还出现明显的心脏肥大，心房ANF浓度降低但含量未变，心室ANF浓度和含量增加。尽管血浆ANF浓度较高，但在所有观察时间段，主动脉-腔静脉分流大鼠的红细胞压积较低，在1和2周时尿钠排泄和尿量减少，在4、8和16周时有减少趋势。16周时，主动脉-腔静脉分流动物的体重高于假手术对照组。
（1）长期升高的心脏充盈压不仅刺激了ANF释放，还刺激了每个心腔的ANF合成，这反过来又导致主动脉-腔静脉分流大鼠血浆ANF浓度升高；（2）在主动脉-腔静脉分流大鼠中，肾脏对内源性ANF的反应减弱以及钠和水潴留明显。神经激素血管收缩系统的激活和血浆ANF浓度逐渐降低可能导致该心力衰竭实验模型不同阶段的钠和水潴留。
