ABSTRACT
Objective To verify the feasibility of a rat model of acute hypertension, and to observe the imaging findings at 7.0T MR scanner of the model.Methods In experimental group, the rats were scanned at 7.0T Bruker MR scanner when phenylephrine was injected continuously to evoke an acute hypertension state.The real time blood pressure was monitored through a femoral arterial catheter connected to a pressure transducer.The control group was infused with saline.T2WI, DWI and T1 mapping were performed in the two rat groups.ADC maps and T1 maps were acquired after image post-processing, and a voxel wise analysis and a ROI analysis were applied.The brain morphology change was evaluated by HE staining.The blood-brain barrier permeability was evaluated by Evans blue staining.Results The T2 images and DWI images of the experiment group showed no abnormal signal intensity changes observed by naked eyes.But ROI analysis of the ADC maps showed that the brain ADC values of the experiment group was higher than the control group (t=3.291,P0.05).The blue dye region was only performed in the experimental group,the results of HE staining corresponded with vasogenic brain edema.Conclusion Continuous infusing of phenylephrine hydrochloride can induce a rat model of acute hypertension.Vasogenic edema and blood-brain barrier permeability change can be observed in the rat model, and the imaging distribution of vasogenic edema can be detected by MRI.