However, at the oral cavity, thoracic esophagus, ascending colon, descending colon and the rectum, the muscularis externa is instead bounded by adventitia . ( The muscularis externa of the duodenum is bounded by both tissue types . ) Generally, if it is a part of the digestive tract that is free to move, it is covered by serosa, and if it is relatively rigidly fixed, it is covered by adventitia.
22.
Thus, BLT2 may be responsible in part or whole for mediating the growth-promoting and anti-apoptosis ( i . e . anti-cell death ) activities of 15 ( S )-HETE in cultured human breast cancer cells, human cancer colon cells, human hepatocellular HepG2 and SMMC7721 cancer cells, mouse 3T3 cells ( a fibroblast cell line ), rat PA adventitia fibroblasts, Baby hamster kidney cells, and diverse types of vascular endothelial cells.
