| Objectives:To study the intravenous injection of recombinant adeno-associated viral type 9（rAAV9）mediated calcitonin gene-related peptide（CGRP）gene on spontaneously hypertensive rats（SHR）Blood pressure,left ventricular fibrosis,kidney damage.Methods:Sixteen spontaneously hypertensive rats（SHR）were randomly divided into 4 groups,4 rats in each group,divided into control group,empty vector group,CGRP group,and benazepril group.Measured the blood pressure of spontaneously hypertensive rats,Plasma CGRP content and urine microalbumin content in each group of rats were sacrificed.Rats were killed at week 8.The expression of CGRP,left ventricular weight index,left ventricular collagen volume fraction（CVF）were measured in each of group,and the renal tissues were observed pathomorphology.Results:1.At the 3rd,6th and 8th week,the plasma CGRP concentration in the CGRP group was significantly higher than that of other three groups（P<0.05）,and the CGRP content in the benazepril group was higher than that in the control group and empty vector group（P<0.05）.The left ventricular CGRP expression was highest in the CGRP group,followed by the benazepril group,and the control group and the empty vector group were the least.2.The systolic blood pressure of CGRP group decreased in the third week after injection,and there was significant difference between CGRP group and control group and empty vector group in the third week and the seventh week（P<0.05）;there was no significant difference between benazepril group and CGRP group at each time point（P>0.05）.The systolic blood pressure of benazepril group decreased from the third week to the eighth week after administration,which was significantly different from that of the control group and the empty vector group（P<0.05）.3.There was a moderate negative correlation between systolic blood pressure and plasma CGRP concentration.4.CGRP group,Benazepril group have significant difference in CVF with control group and empty vector group（P<0.05）.5.At the 3rd,6th and 8th week,the concentration of microalbumin in CGRP group was significantly lower than that in the other three groups（P<0.05）.At the third week,there was no significant difference in the concentration of urinary microalbumin between the benazepril group and the control group and the empty vector group（P>0.05）.At the sixth and eighth weeks,the concentration of urinary microalbumin in the benazepril group was lower than that in the control group and the empty vector group（P<0.05）.At the third and sixth weeks,there was no significant difference between the CGRP group and the benazepril group（P>0.05）.At the eighth week,the concentration of urinary microalbumin was lower than that in the benazepril group There was significant difference between the two groups（P<0.05）.In the control group and empty vector group,the basement membrane and interstitial sclerosis of renal tubules were observed,and the epithelial cells of renal tubules were swollen.In CGRP group and benazepril group,there was no obvious pathological change of renal tubules and glomeruli.Conclusion:1.After rAAV9-CGRP gene was injected into the tail vein of SHR,the plasma CGRP increased from the third week to the eighth week.The systolic blood pressure decreased from the third week to the seventh week.2.rAAV9-CGRP gene can reduce left ventricular myocardial fibrosis,urinary microalbumin and renal tubule injury.Its protective effect is similar to benazepril. |
