The Effect Of Different Degree Acute Normovolemic Hemodilution On The Function Of Glomcrulus And Nephric Tubule In Rabbit

Objective To investigate the effect of different degree acute normovolemic hemodilution with 6%HES on the function of rabbits'kidney and make a guidance for the use of hemodilution in clinic.Methods Thirty-two major rabbits were anesthetized with 20%urethane 5ml·kg-1 and mechanically (vt=15mlkg-1, f=30bpm). Blood were withdrawn from femoral artery and simultaneously replaced by intravenous infusion of equal volume of 6% hydroxyethly starch until achieving target HCT. Body temperature were maintained on 37 degree. The animals were randomly were randomly assigned to four equal groups with 8 animals in each group; Group N was control group without hemodilution; HCT in Group A, B and C were targeted with 24%,18% and 12% respectively. Hemodilution were performed at 30min following the empirical formula. Blood sample were taken before hemodilution, and at 2 hours,4 hours and 8 hours after hemodilution for determination of plasma BUN,Cr,Cystatin C and NAG in urine. At the end of the experiment, renal tissue was obtained for light and electron microscopic examination.Results There were no obvious difference in the serum level of CysC and in the urine of NAG/Cr between Group A and N(P>0.05). In Group B, levels of CysC increased at 8 hours(T3) while NAG/Cr stepped up from 2 hours(T1) to 8 hours(T3) compared to baseline(T0) after hemodilution (P<0.05); As for Group C, the levels of Cys C and NAG/Cr significantly stepped up from 2 hours(T1) to 8 hours(T3) after hemodilution (P<0.05). There were no significant difference in BUN and SCr between all groups(P>0.05). MDA raised significantly in the nephridial tissue while SOD decreased in Group C(P<0.05).Conclusion When targeted HCT with 24%, ANH do not disturb normal renal function. If the targeted HCT is 18%, we may observe that focal edema and some other hypoxia lesions in proximal convoluted tubule at 8 hours after hemodilution while no change in glomcrulus. More deeper, more longer, there are more aggravation in renal injury. When the hemodilution for 12% target HCT is performed, glomcrulus filter membrane barrier can be impaired and proximal convoluted tubule will appear apomorphosis, necrosis and other hypoxia injuries.