Effect Of Blood Pressure Variability On The Expression Of Trpc6in Aorta And Myocardium In Sprague Dawley Rats

Background and Objective: Blood pressure variability(BPV) is one ofthe basic physiological characteristics of human Beings.High BPV isusually observed in patients with hypertension,but person withouthypertension could also have it.BPV involves some environmental andheredity factors.High BPV which is lack of effective therapy could bringadverse effects to the target organ damage and prognosis as blood pressurelevels.Studies in recent years have found that the C6subtype of canonicaltransient receptor potential(TRPC) is closely related to the essentialhypertension.However,the mechanism of TRPC6is distinguished from thetraditional pathogenesis of hypertension.The specific mechanism of TRPC6is supposed to play a role in the formation of BPV.In the presentstudy,through building the abnormal blood pressure variability model bysinoaortic denervated(SAD), we intent to investigate the effect of bloodpressure variability (BPV) on expression of TRPC6in aorta andmyocardium in SD rats, determining the association between TRPC6andBPV,and to provide experimental proof for searching more effective treatment of BPV in clinical work.Methods:24-hour blood pressure were measured eight weeks afteroperation while the rats are conscious and unrestrained.The mean andstandard deviation of24-hour systolic and diastolic blood pressure werecalculation with standard deviation as the indicators.The left ventricle massindex (LVMI) of TRPC6in both groups is measured;the expression ofmessenger ribonucleic acid(mRNA) and protein of TRPC6weredetermined by reverse transcription polymerase chain reaction(RT-PCR),western blot and immunohistochemistry respectively.Results:Compared with sham group,the24-hour average systolicblood pressure(SBP) and diastolic blood pressure(DBP) had no significantdifference in SAD group.Compared with the sham group, the24-hoursystolic blood pressure standard deviation [（8.19±3.78）vs（3.35±0.53）mmHg], diastolic blood pressure standard deviation [（8.19±3.78）vs（3.35±0.53）mmHg], LVMI [（2.19±0.06）vs（1.71±0.04）mg/g,P<0.05]and the expression of TRPC6mRNA and protein in aorta andmyocardium were significantly increased in SAD group(all P<0.05).Conclusion: In SAD group, the expression of TRPC6mRNA andprotein were significantly increased in both aorta and heart, whichdemonstrated that increased BPV is associated with increased expression ofTRPC6, TRPC6may be involved in the regulation of BPV in SD rats, andcould have played an important role in pathologic cardia hypertrophy.