Elevated gastrin secretion by in vivo gene electroporation in skeletal muscle

Whether or not in vivo acne transfer of gastrin gene into skeletal muscle b y electroporation could modify gastrin secretion was examined. The expressi on plasmid vector, either pMEPrGaspA encoding the rat gastrin acne or pEGFP -N1 encoding the GFP reporter gene was injected into M. rectus abdominis bf rats or M. biceps formis of mice. Subsequently, square electric pulses of direct current were applied six times at 25 V with a loading period of 100 msec per pulse. Clear foreign gene expression in the skeletal muscle was de monstrated by. both GFP fluorescence and immunostaining of rat gastrin. Tim e course changes in plasma gastrin levels after transfection revealed that in rats, gastrin gene transfer significantly increased the plasma gastrin l evel for 4 weeks post-transfection (P<0.05), but the difference diminished at the end of the 10-week period. In mice, plasma gastrin level elevated si milarly for 3 weeks, and pH of gastric contents decreased in the gastrin ge ne transfected group compared with the control counterpart (P<0.05). These findings suggest that localized in vivo gene transfer by electroporation al lows skeletal muscle to become an artificial endocrine tissue for hormonal manipulation of animals.