Experimental Study On Cerebrovascular Reserve Capacity By Prfusion Weighted Imaging Combined With "Acetazolamide Stress Test" In SHR

Objective:To assess the cerebrovascular reserve capacity by MR perfusion weighted imaging combined with "acetazolamide stress test" in SHR and explore the histological basis of CRC expressed by medical imaging.Methods: Detected the changes of PCO2 dynamically by blood gas analysis to identify the time of the peak value after administrated the ACZ orally; PWI was performed respectively before and after acetazolamide in 3 groups, including WKY (12-week-old, n=10), SHR (12-week-old, n=10) and SHR (20-week-old, n=10). Chose the ROI in the bilateral frontal lobe to measure the value of rCBV, rCBF and MTT, and deduced the index of CRC. Statistical analysis was performed. Observe the arteriole wall, the numbers of small vessels and blood capillary under the light microscope.Results:1,The PCO₂ came to peak at the 2.5-hour after the WKY administrated the ACZ orally.2,In both resting and ACZ test state, no statistic differences in all the values of rCBV,rCBF,MTT and ( rCBV₂-rCBV₁) /rCBV₁, (rCBF₂-rCBF₁) /rCBF₁, ( MTT₂-MTT₁) /MTT₁ betweenthe left and right hemisphere among the three groups (P>0.05) .3,Before ACZ, significant statistic differences between the WKY and SHR(12-week-old),and between SHR(12-week-old) and SHR(20-week-old) in the values of rCBV and rCBF (P<0.05) . Significant statistic differences between WKY and SHR(20-week-old) in the valueof MTT (P<0.05) .4, After ACZ, significant statistic differences between WKY and SHR(20-week-old), andbetween SHR(12-week-old) and SHR(20-week-old) in the rCBV value (P<0.05) .Significant statistic differences in rCBF and MTT between every two of the three groups (P...