动物造模,脓毒症大鼠 z-bio 2021-10-28 321

　　Objective: To investigate the mechanism of diaphragmatic diastolic dysfunction in rats with acute sepsis.

　　Method: 36 male clean SD rats. Random number table method is divided into: sham operation group (S group) 12 rats, and model (CLP group) 24 rats. The cecal ligation and perforation operation was performed on the model to replicate the sepsis model. After the model was successfully modeled, they were randomly divided into the sepsis CLP-6 h group and the sepsis CLP-12 h group, each with 12 animals, each at 6 h after surgery And 12 hours to measure single stimulation muscle twitch (Pt), maximum tonic contraction (Po), half-diastolic time (1/2RT), contraction time (TPT), maximum systolic ascent rate (+dF/dt) and maximum diastole Decline rate (-dF/dt); Fura-2 method was used to determine the maximum uptake and release rate of diaphragmatic sarcoplasmic reticulum calcium, and Western blotting was used to detect the expression of sarcoplasmic reticulum SERCA1, SERCA2 and RyR.

　　Results: The half-diastolic time of rats in the 6 and 12 h group was significantly longer than that in the S group, and the -dF/dt decreased significantly (P<0.01), but only in the 12 h group rat diaphragm +dF/dt, Pt, The peak release rate of Po and sarcoplasmic reticulum calcium was significantly lower than that of the S group (P<0.01), 6="" p="">0.05); the expression of SERCA1 and RyR in the diaphragm of the rats in the 12 h group was significantly decreased (P<0.01) serca2="" and="" -atp="" enzyme="" activities="" did="" not="" change="" significantly="" p="">0.05).

　　Conclusion: Diaphragm contraction and diastolic function are significantly impaired within 12 hours of acute phase in septic rats. Diastolic dysfunction may be related to decreased sarcoplasmic reticulum calcium uptake function and low expression of SERCA1, and decreased sarcoplasmic reticulum release and uptake function and RyR expression Together they lead to a decline in contractile function.