TY  - BOOK
AU  - 
AU  - Bisnar, Paul O.
ED  - 
ED  - 
ED  - Philippine Journal of Science 135(2): December 2006. p.73-81
ED  - 
SN  - 2
PY  - 0000///46
CY  - 
PB  - 
KW  - 
KW  - 2
KW  - 0
KW  - 6
KW  - 20
KW  - Microcolony
KW  - Cyclooxygenase inhibitors
KW  - Radiation
KW  - sears0
N1  - ABSTRACT :  The regulation of tissue homeostasis in the gastrointestinal epithelium after epithelial injury focuses on the prostaglandins (PGs) as its major mediators. The two cyclooxygenase isoforms, Cox-1 and Cox-2, catalyze synthesis of PGs. Cox-1 is the predominant cyclooxygenase isoform found in the normal intestine. In contrast, Cox-2 is present at low levels in normal intestine but is elevated at sites of inflammation, and in adenomas and carcinomas. To study the effects of various commercially-available cox-inhibitors (Ketorolac: Cox-1 selective; Celecoxib: Cox-2 selective; and Indocid: Cox-1/2 non-selective), we determine mouse crypt epithelial cell fate after genotoxic injury with whole-body gamma-ray exposure at 15 Gy. Intestinal tissues of mice treated with Cox-2 inhibitors that showed invariable apoptotic event, however, have increased occurrence of regenerating cells. Our results suggest a potential application of Cox-2 selective inhibitors as radioprotective agent for normal cells after radiotherapy; 5
ER  -