الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 219 |  |  |
| | | from | 219 | | |
Abstract
The current study is the first to examine TQ in pyloric ligated rats subjected to I/R. The first series (7 groups) was used to test TQ modulatory effect on both acid-related parameters, as well as the antioxidant ones; besides ulcer index and histological examination. The first group served as the normal control, the second was the sham group, and the third presented the positive control one. In this group the pylorus area of anaesthetized animals was ligated and consequently subjected to ischemia by clamping celiac artery for 30 min., followed by declamping the artery to allow for reperfusion. After 2 hours animals were sacrificed and their gastric juice and mucosa were collected for parameters’ determination. Groups 4 and 5 received TQ (10 or 20 mg/kg), group 6 was treated by OMP (20 mg/kg) and the last group received lower doses of both TQ & OMP (10 mg/kg each). All treatments were administered intraperitoneally 30min. before operation.
The acid-related parameters were assessed in the collected gastric juice and they include mucin content, titratable acidity, acid output, peptic activity, as well as H+/K+-ATPase (proton pump). The latter is evaluated for the first time as a potential mechanism for the TQ anti-lesive action. On the other hand, the free radical/antioxidant character of TQ was quantified in the mucosal homogenate by measuring lipid peroxide, GSH, and SOD, in addition to NO and MPO levels/ activity. MPO is used to indicate intracellular invasion of neutrophills. Gross mucosal damage was assessed macroscopically and was presented as the ulcer index (UI); this was substantiated by histological examination. The gastric mucosal NO level was recorded, as mentioned previously, to clarify the possible intervention of NO during ulcer induction and its modulation by thymoquinone. Since in the first series the NO determination method did not clarify, whether NO resulted from either cNOS or iNOS, hence, another series of animals were involved. In these groups AMG, a selective iNOS inhibitor, was injected 30 min. before pyloric ligation/ischemia alone or concomitantly with the different treatment regimens. The present study showed that TO, especially in the higher dose, opposed the I/R-mediated alterations in almost all parameters, results that were nearly comparable to the standard drug used.