Burtea C, Gatina R, Stoian G, Mardare M, Dumitru I F, Dragomir C T
Institute of Pathology and Medical Genetics 'Victor Babes', Bucharest, Romania.
MAGMA. 1998 Dec;7(3):184-98. doi: 10.1007/BF02591336.
Magnetic resonance techniques afford a significant advantage for noninvasive diagnosis of cardiovascular pathology. The purpose of our present study was to assay the proton nuclear magnetic resonance (1H-NMR) sensitivity in the differential diagnosis of certain endocrine cardiovascular complications. In this context, we investigated the water state and content in the hypertrophied myocardium. Male and female Wistar rats were treated with different hormones (hydrocortisone acetate, testosterone, estradiol, thyroid hormones) in combination with isoproterenol (a synthetic catecholamine that induces myocardial ischemia and hypertrophy). The animals were sacrificed after 20 days of treatment and samples of integral myocardium and left ventricular myocardium were analyzed on a 1H-NMR AREMI spectrometer (0.6 T; proton resonance at 25 MHz). The estimation of T2 was made by Carr Purcell-Meiboom-Gill pulse sequence. The data were fitted to a bi-exponential curve, yielding short (T21) values for bound water and long (T22) values for free water. In order to evaluate the myocardial hypertrophy, the following ratios were calculated: integral myocardium to body weight; left ventricle to body weight; left ventricle to integral myocardium. The first two ratios were also calculated for dried tissue, in order to estimate its contribution to myocardial hypertrophy. Our findings demonstrate that myocardial hypertrophy is associated with a decrease of T22, as a consequence of the increase in the dried component (i.e. proteins) of the tissue, while the total tissue water (H2Ot%), measured by gravimetry) was not significantly modified. Nevertheless, it is reasonable that the increase in the protein content would be proportional with the increase in H2Ot%. The decrease of T21 seems to be proportional with the level of left ventricle hypertrophy in female groups. The 1H-NMR measurements were much sensitive for the differential diagnosis of myocardial hypertrophy in the case of left ventricle.
磁共振技术为心血管疾病的无创诊断提供了显著优势。我们当前研究的目的是测定质子核磁共振（1H-NMR）在某些内分泌性心血管并发症鉴别诊断中的敏感性。在此背景下，我们研究了肥厚心肌中的水状态和含量。将雄性和雌性Wistar大鼠用不同激素（醋酸氢化可的松、睾酮、雌二醇、甲状腺激素）与异丙肾上腺素（一种诱导心肌缺血和肥大的合成儿茶酚胺）联合处理。处理20天后处死动物，并在1H-NMR AREMI光谱仪（0.6 T；25 MHz质子共振）上分析完整心肌和左心室心肌样本。通过Carr Purcell-Meiboom-Gill脉冲序列进行T2估计。数据拟合为双指数曲线，得出结合水的短（T21）值和自由水的长（T22）值。为了评估心肌肥大，计算了以下比率：完整心肌与体重之比；左心室与体重之比；左心室与完整心肌之比。还计算了干燥组织的前两个比率，以估计其对心肌肥大的贡献。我们的研究结果表明，心肌肥大与T22降低有关，这是由于组织干燥成分（即蛋白质）增加所致，而通过重量法测量的总组织水（H2Ot%）没有显著改变。然而，蛋白质含量的增加与H2Ot%的增加成比例是合理的。T21的降低似乎与雌性组左心室肥大程度成比例。1H-NMR测量对左心室心肌肥大的鉴别诊断非常敏感。
