Résumé
<p><b>OBJECTIVE</b>To evaluate the expression of nitric oxide synthase III (NOS III) mRNA in the heart, aorta, kidney and liver of spontaneously hypertensive rats (SHR).</p><p><b>METHODS</b>Two hundred and ninety-four total RNA samples were obtained from the tissues of ventricle, aortic smooth muscle, kidney and liver of SHR and normotensive rats (Wistar-Kyoto rats, WKY). RNA array was used to determine the mRNA levels of NOS III of the two groups.</p><p><b>RESULTS</b>Compared with WKY, the systolic blood pressure increased significantly in SHR at 6-week-old, 8-week-old, 10-week-old and 12-week-old [(158.50 +/-7.69 vs 108.67 +/-5.89) mmHg, (174.33 +/-4.46 vs 128.50 +/-4.97) mmHg, (198.00 +/-13.45 vs 142.00 +/-3.58) mmHg, (216.67 +/-8.91 vs 141.17 +/-4.92) mmHg, P<0.01], and the ventricle/body weight ratio was significant higher at 10-week-old and 12-week-old [(4.08 +/-0.17 vs 3.59 +/-0.11, 4.05 +/-0.18 vs 3.40 +/-0.19)mg/g, P<0.01]. In the heart tissue and the kidney, the mRNA levels of NOS III were significantly increased at 6-week-old, 8-week-old, 10-week-old and 12-week-old (1.12 +/-0.18 vs 0.90 +/- 0.15, 1.46 +/- 0.34 vs 1.06 +/-0.18, 1.66 +/- 0.31 vs 1.21 +/- 0.30, 1.98 +/- 0.40 vs 1.31 +/-0.38, P <0.05) and at 4-week-old, 6-week-old, 8-week-old, 10-week-old and 12-week-old (1.10 +/- 0.21 vs 0.81 +/-0.11, 1.28 +/-0.18 vs 0.95 +/-0.13,1.31 +/-0.23 vs 0.99 +/-0.23, 1.70 +/-0.30 vs 1.08 +/-0.25, 1.83 +/-0.33 vs 1.15 +/-0.20, P<0.05 or P<0.01), respectively. There was no significant difference of the NOS III expression in the liver and no significant signals were detected in the aortic smooth muscle.</p><p><b>CONCLUSION</b>The results provide the evidence of the increased expression of NOS III in different tissues in SHR and suggests the progressive nature of essential hypertension.</p>