[Establishment of a diabetic-hypertensive rat model]

This study is to establish a diabetic-hypertensive model in rats. After the induction of diabetes by streptozocin (STZ), rats were maintained with free access to rat chow and 1% NaCl drinking water. Blood pressure was monitored at conscious state by tail-cuff weekly till it was 50 mmHg higher than normal animal steadily. Finally, blood pressure was measured by catheterization of the right carotid artery and plasma ET-1 and Ang II, kidney Ang II and angiotensinogen or preproendothelin gene expression in liver or aorta were assayed separately. STZ-diabetic rats that maintained with 1% NaCl drinking water exhibited obviously increasing blood pressure since the third week. Then the pressure reached 150 mmHg at the 6th week and was maintained until the 11th week. Till the 12th week, the blood pressure reached to higher than 160 mmHg. In addition, these high blood pressure rats were accompanied with increased blood plasma ET-1 and Ang II and augmented gene expression levels of angiotensinogen in kidneys and preproendothelin in aorta tissues. Loading sodium chloride chronically to STZ-diabetic rats could prepare a diabetic-hypertensive rat model.