Characteristics Of Blood Pressure Variability In Three Different Kinds Of Hypertensive Rats

Blood pressure variability(BPV)refers to the unstability of blood pressure(BP) during a certain period of time,high BPV is one of the hemodynamic character in spontaneously hypertensive rat(SHR),Lyon hypertensives rat(LHR)etc. Studies have shown that the modulating mechamism of BPV is different from BP,and BPV plays an important role on organs damage. However,it is still uncertain about whether BPV is all increased,and what characteristics BPV have in different kinds of hypertensive rats. Using computerized analysed system of BP,in this study,three different kinds of hypertensive rats,which were caused by Deoxycorticosterone acetate(DOCA),two kidney one clip(2K!C) and N w -nitro-L-arginine methylester (L-NAME). The characteristics of BPV,and its relationship with organs damage and concentration of plasma active substance were analyzed.Hemodynamic parameters of three different kinds of hypertensive rats.1 DOCA hypertensive rats(D Compared with control group,the 24h BP and BPV,day-time BP and BPV,night-time BP and BPV were increased significantly;the 24h HPV,day-time HPV and night-time HPV were also markely elevated;for HP,only day-time HP prolonged obviously.(D The circadian rhythm showed that during day-time BP was lower than during night-time,whereas BPV was right the opposite to BP;the highest level for SBP appeared between 10 am and 12 am,for DBP between 12 am and 2 am. However,the highest peek for both SBPV and DBPV was from 6 am to 8am.(D The 24h BPV,day-time BPV and night-time BPV of DOCA hypertensiverats was higher compared with either L-NAME hypertensive rats was higher when compared with either L-NAME rats or 2K1C hypertensive rats.2 L-NAME hypertensive rats(1) Compared with control group,the 24h BP and BPV,day-time BP and BPV,night-time BP and BPV were rised markedly.(2) The circadian rhythme for BP and BPV disappeared. The highest level for SBP appeared between 8 pm and 10 pm;for DBP between 4pm and 6 pm;for SBPV between 6 am and 8 am;for DBPV between 4 pm and 6 pm.(3) Compared with DOCA 2K1C hypertensive rats,the 24hDBP,day-time DBP and night-time DBP were higher in L-NAME hypertensive rats.3 2K1C hypertensive rats Compared with control group,the 24h BP and BPV,day-time BP and BPV,night-time BP and BPV were increased obviously;the 24h HPV,day-time HPV and night-time HPV also raised significantly;for up,only day-time HP markedly prolonged.(2) The differentiation of circadian rhythm of both BP and BPV between day-time and night-time were meaningless;the highest level of SBPV appeared between 12 am and 2pm,for DBPV between 6am and Sam.Baroreflex sensitivity of three different kinds of hypertensive ratsWith modulated smyth method,the Baroreflex Sensitivity was measured. Compared with control group,the BRS of DOCA,L-NAME,and 2K1C hypertensive rats decreased significantly;however there was no relationship existed between BRS and hemodynamic paraments among three different kinds of hypertensive rats.Blood pressure variability and organs damage among three different kinds of hypertensive rats.Using computerized analysed system combined with morphologic detection andlight-microscopic observation,the heart,kidney and tail-aorta were examed. Compared with control group rats,cardiac,nephric and tail-aortic damage had developed among three different kinds of hupertensive rats. In general,cardiac muscular and nephric interstitium fibrosis were the main characteristics appeared both in DOCA and L-NAME hypertensive rats;whereas in 2K1C hypertensive rats main damages developed in the kidney.Blood pressure variability and plasma active substance in three different kinds of hypertensive rats.Plasma ET-I and Angll concentration were measured with RIA,and IL-1 and TNF were detected by ELISA.1 Compared with control group,DOCA hypertensive rats:the plasma level of ET-1,IL-1B and TNF were significantly increased,Angll was decreased;L-NAME hypertensive rats:the plasma level of IL-IB and TNF were markedly raised;2K1C hypertensive rats:only the plasm...