Effect Of Arginine Vasopressin On Arterial Baroreflex And The Function Of Organs In Septic Rat

ObjectiveTo investigate the effects of central and peripheral supplement of arginine vasopressin (AVP) on arterial baroreflex (ABR) function in sepsis rats, and explore the effect of arginine vasopressin (AVP) on protecting organic function in septic rats.Methods1. The sepsis model was induced in Male SD rats by cecal ligation puncture (CLP).2. The ABR functions were determined and AVP-like immunoreactivities were detected by immunohistochemical method in supraoptic and paraventricular nucleus of CLP (n=18) or sham operation (n=4) rats after 4 h,8 h or 12 h of CLP.3. In another 20 CLP rats, AVP was supplemented by continuous intravenous infusion or intracerebroventricular injection before ABR functions were determined.4. After injection, all rats were killed, and leaving each animal's blood, then ALT,AST,ALP,BUN and Cr to be determinated.Results1. Sepsis produces a gradual decrease in ABR function, as well as a gradual reduction in AVP expression ratio in supraoptic and paraventricular nucleus.2. Compared with sham operation group, inject AVP(50 ng) into lateral ventricles(LV) 8 hours after CLP caused an increase in ABR, MAP and HR. Continuous infusion of AVP at a rate of 2 ng/kg/h 6 hours after CLP generated a profound increase in MAP and ABR, as well as a decrease in HR.3. Sepsis produce a gradual increase in ALT,AST,ALP,BUN and Cr from 4 h after CLP, and more significantly after. Compared with sham operation group,continuous infusion of AVP at a rate of 2 ng/kg/h 6 hours after CLP generated a profound decrease in ALT,AST,ALP,BUN and Cr. But inject AVP(50 ng) into lateral ventricles(LV) 8 hours after CLP caused an increase in ALT,AST,ALP,BUN and Cr.Conclusion1. In sepsis, the reduction of AVP expression ratio in supraoptic and paraventricular nucleus induces a decrease in ABR, and that this may contribute to promote sepsis to septic shock..2. Continuous infusion of AVP in the initial phase of sepsis can facilitate ABR function and prolong the time from sepsis to septic shock.3. We assessed the function of liver and renal in relation to plasma vasopressin levels in the rats with endotoxemia. Continuous infusion of AVP at the initial phase of septic shock can protect some organs' function.