Experimental Study On The Relationship Between Essential Hypertension And The Expression Of CD13in Kidney And Circulation Of SHR Rats

Objective:to preliminarily study the expression of CD13in hypertension and the role in essential hypertention.Methods:32SPF male spontaneously hypertensive rats of4weeks were used as experimental model while Wistar-Kyoto rats as the control group.Both SHR and WKY rats were divided into4groups according to the simple random method and each group has8rats. They were obervased at4weeks(period0),6weeks(starting period of hypertension),10weeks(forming period of hypertension),23weeks(end period of target orgen damage).Use noninvasive tail artery blood pressure measuring instrument for dynamically monitoring the blood pressure of SHR and WKY rats. ELISA was uesd to dynamically detect24h urine protein of the rats. Total RNA of renal tissue was extracted and reverse transcripted into cDNA. Use the method of RT-PCR to detect the index of CD13in the rat’s kidney dynamically. The index of CD13protein in the rat’s kidney was detected dynamically by the method of immunohistochemistry after renal tissue was wrapped into wax block in the form of longitudinal section through cortex and medulla. Use the method of ELISA to detect the index of CD13, AngⅢ and Ang IV in the rat’s plasma. HE and MAS SON staining was used to detect the renal pathological changes of the rats.Results:The weight of SHR rats were lower than the wild-type WKY rats during the observation period. They are respectively(160.2±5.3vs.186.8±6.8) g,(230.6±13.5vs.252.3±5.5) g and (310.7±9.1vs.357.4±7) g in6weeks,10weeks and23weeks, there were significant differences between two groups(P<0.05). The blood pressure of SHR rats was also higher than the wild-type WKY rats in6weeks,10weeks and23weeks. They are respectively(128.8±10.3vs.109.1±3.8)mmHg,(152.6±8.6vs.115.5±11.2) mmHg,(203.9±13.2vs.112.9±6.9) mmHg, there were significant differences between two groups (P<0.05). The index of CD13mRNA expression in SHRs’kidney was significantly higher than that of wild-type WKY rats in10weeks and23weeks (P<005). The index of CD13protein expression in SHRs’ kidney was higher than wild-tyer WKY rats too. They are respectively0.42±0.12vs.0.25±0.15,0.57±0.13vs.0.38±0.09,0.73±0.12vs.0.37±0.19, in6weeks,10weeks and23weeks. There were significant differences between two groups(P<0.05).The index of CD13 expression in SHRs’ plasma was lower than that of WKY rats. They are respectively (107.4±22.3vs.147.1±25.5)ng/L and (87.04±20.7vs.150.1±31.2) ng/L in10weeks and23weeks. There were significant differences between two groups (P<0.05). In addition, there are negativecorrelation between the index of CD13in plasma of SHRs (r=-0.758, P<005); There are positive correlation between the index of AngⅢ and the blood pressure of SHRs (r=0.711,P<0.05);There are negativecorrelation between the index of AngⅣand blood pressure of SHRs (r=-0.732, P<005). There are negative correlation between the dynamic index of CD13and AngⅢ in plasma of SHRs too (r=-x, P<0.05); There are positive correlation between the dynamic index of CD13and AngⅣin plasma of SHRs too (r=y, P<0.05).Masson staining showed that The collagen deposition around renal microvascular and renal tubular interstitial in SHRs was higher than wild-type WKY rats at10week and23weeks.Conclusion:CD13may plays independent roles in kindney and the circulatiory system and both of these involved in regulating the blood pressure and pathological changes.