Six weeks after the renal artery clipping procedure, the animals were killed and the stomach was immediately removed, opened (along the long curvature) and rinsed in saline. Tissue samples were collected from the pyloric region of the stomach. They were fixed in 4% buffered formalin for 24 hours at + 4 8C, and processed routinely for embedding in paraffin. Sections were cut at 4 mm in thickness, and stained by hematoxylin–eosin (H+E) for general histological examination.