Expression of serum response factor in normal rat gastric mucosa.

Serum response factor (SRF) is a transcription factor that is involved in cell proliferation, muscle and neuron development and maintenance. Its expression in gastric mucosa remains unknown. In this study we demonstrated that SRF is expressed in normal rat gastric tissue as two isoforms and localized mainly to smooth muscle cells of muscularis mucosae and its extensions into the lamina propria, to muscularis propria, and musculature of the vascular system. To a lesser extent, SRF is also expressed in the gastric epithelium of the mucosal neck area (proliferative zone) and in the endothelial cells of microvessels. These data suggest that the main role of SRF in normal gastric tissue is to maintain muscular support and contraction and possibly epithelial regeneration.