Abstract： Objective To observe the intervention role of normal lymph plasma on renal and hepatic micro-regional blood perfusion in rats with endotoxic shock. Methods Thirty male Wistar rats were equally divided into control group,model group and lymph plasma group by random digits table.The latter two groups were injected intravenously with lipopolysaccharide(LPS,15 mg/kg) to duplicate endotoxic shock model,and equal amount of normal saline was given in the control group instead of LPS.Fifteen minutes after the reproduction of model,normal lymph plasma in an amount of 1/15 of blood volume was infused in lymph plasma group.In control and model groups,normal saline was given instead of lymph plasma.Blood pressure was monitored continuously for 6 hours after LPS injection(or normal saline) in all groups,and the micro-regional blood perfusion of the kidney and liver was also observed at the same time with laser Doppler flowmetry.The survival time among groups was compared. Results After injecting LPS,the blood pressure of both model and lymph plasma groups declined quickly,and in model group,it gradually descended after a brief elevation.The blood pressure of lymph plasma group although was lower than that of control group at early and later stage,but it was still higher than that of model group.After LPS injection,the micro-regional blood perfusion(PU) of kidney and liver in model group and lymph plasma group were also decreased significantly compared with the control group(kidney:559.90±111.87,577.50±91.49 vs.672.60±50.81;liver:160.50±54.17,163.56±34.04 vs.232.30±34.23,all P<0.05).The blood perfusion of kidney in two groups was increased markedly after 30 minutes compared with control group,and the high level was maintained in the lymph plasma group up to 75 minutes,then it maintained at the level of control group.However,in model group,the blood perfusion was significantly reduced at 120 minutes,and it was significantly lower than control group after 210 minutes.The renal micro-regional blood perfusion(PU) in lymph plasma group was significantly higher than that of model group at 270360 minutes,especially after 330 minutes(330 minutes:615.44±98.71 vs.364.40±146.76,360 minutes:584.56±104.72 vs.307.11±143.11,both P<0.05).The liver blood perfusion in both groups became normal at 30 minutes,and in model group it declined progressively at 270 minutes.In lymph plasma group the liver blood perfusion(PU) was markedly increased compared with model group,especially after 330 minutes(330 minutes:224.67±20.65 vs.172.90±46.74,360 minutes:218.56±20.40 vs.158.52±44.71,both P<0.05).In model group,the onset of decrease in perfusion(minutes) in the kidney was significantly earlier than that of liver(123.00±68.85 vs.282.00±96.90,P<0.01).Survival time(hours) was markedly prolonged in lymph plasma group than that of model group(11.80±2.67 vs.7.21±1.33,P<0.01). Conclusion Normal lymph plasma may play a beneficial intervention role in kidney and liver tissue hypoperfusion,and it ameliorates hypotension and prolongs survival time in endotoxic shock.