Abstract:The adenosine monophosphate activated protein kinase(AMPK)is a key regulator of catabolic and anabolic processes in energy metabolism. This study was conducted to construct and select the effective siRNA interference vector for porcine AMPKα gene. Two pairs of porcine AMPK α-specific double-strand siRNA(dsRNA) primers were designed and inserted into pSilencer 4.1-CMV neo Vector after annealing. The vectors were then transfected into porcine intramuscular preadipocytes by lipofection 2000, AMPKα and lipolitic enzyme genes HSL(hormone sensitive lipase), ATGL(adipose triglyceride lipase) and CPT1(carnitine palmitoyl transferase) mRNA expressions in these cells were detected by Real-time PCR. The results showed that the AMPKα-specific siRNA vectors RA1 and RA2 were successfully constructed and transfected into porcine intramuscular preadipocytes. The efficiency of RA2 was significantly higher than that of RA1. The mRNA expressions of AMPKα and the lipolitic enzyme genes HSL, ATGL and CPT1 decreased significantly after treatment of porcine intramuscular preadipocytes by vector RA2(P<0.05). It indicated that decomposition of fat and fatty acid oxidation rate decreased in porcine intramuscular preadipocytes when AMPKα mRNA expressions was inhibited. These data will provide insight in the function of AMPK in fat deposition and manipulating gene expression of AMPK in regulating fat metabolism and meat quality in pigs.