Effects of propofol on gastric mucosal cellular apoptosis after resuscitation of hemorrhagic shock in rabbits

Objective To investigate the effects of propofol on gastric mucosal cellular apoptosis after resuscitation of hemorrhagic shock in rabbits.Methods One hundred healthy adult male New Zealand rabbits weighing 2.5-3.0 kg were randomly divided into 5 groups ( n =20 each):group sham operation (group S) ; group hemorrhagic shock ( group M ) and Ⅲ,Ⅳ,Ⅴ 3 propofol groups ( groups P1,2,3 ).Hemorrhagic shock was induced by withdrawing blood from femoral artery.MAP was reduced to 35-40 mm Hg and maintained at this level for 60 min in groups M,P1,P2 and P3.Blood was then transfused back via femoral vein to restore blood volume.In groups P1,2,3 propofol 5 mg/kg was injectel iv at 10 min before ischemia (group P1 ),10 min before (group P2 ) and 20 min of resuscitation (group P3 ) respectively followed by continuous infusion at 20 mg·kg-1 ·h-1 until 90 min of resuscitation.The gastric mucous membrane specimens were obtained at 90 min of resuscitation for macroscopic examination and detection of apoptosis (by TUNEL) and Bcl-2 and Bax protein expression (by immuno-histochemistry).Results Hemorrhagic shock seriously damaged gastric mucous membrane,significantly increased apoptotic index (the number of apoptotic cells/the total number of cells) and Bax protein expression and decreased Bcl-2 protein expression and Bcl-2/Bax ratio in group M as compared with group S.Propofol significantly attenuated hemorragic shock-induced above changes in groups P1 and P2.Concluion Pre- and post-conditioning with propofol can attenuate apoptosis in gastric mucous membrane cells induced by hemorrhagic shock by up-regulating Bcl-2 protein expression and down-regulating Bax protein expression. Key words: Propofol; Shock, hemorrhagic; Resuscitation; Gastric mucosa; Apoptosis