Investigation of the effects of ion channel blockers on arginase, nitric oxide metabolites and ornitine levels in rat liver which is indicued with 7,12-DMBA

In this study, it has been planned to initiate the tumour development process in rats by using 7,12- DMBA which is a carcinogenic agent and to measure the omithine levels and enzyme activity levels of NOS and arginase in liver. The possible effects of ion channel blockers treatment and the changes occured in the levels of omithine, arginase and NOS activities were also investigated. It has been aimed to reach an answer whether induction of NOS activity and/or using ion channel blocker is an additional strategy in cancer treatment. In the study, Sprague Dawley type, 4 months old female rats were used.The rats were divided into three grups as control (n=19), 7,12-DMBA (n=14) and 7,12-DMBA+İKB (n=18) groups. The rats in control groups were treated with only corn oil. The rats in the second group (7,12-DMBA) were treated with a 7,12- DMBA single dose. The rats in the third group were treated with a 7,12- DMBA and RS100642 (ion channel blocker) was injected in the tail vein. After a week from last injection, the rats were sacrificed by decapitation under ether anaesthesia and the liver tissues of the rats were dissected. The tissues perfused with isotonic solution were homogenized in PBS ( PH:7.4) solution.As a result, it has been observed that the balance between the arginase and NOS enzyme systems which used arginine in common were disturbed in favour of arginase significantly. In the third gruop, arginase activity was observed to decrease significantly whereas NOS activity was observed to increase insignificantly.Under the shed of those findings, we considered that using ion channel blockers and/or the induction of NOS activities may have an inhibitory effect on cancer development. But more comprehensive researches are stil needed in the same subject.Key Words: 7,12-Dimethylbenz [a] anthracene, Arginase, Ornithin, Ion Channel Blockers, Nitric Oxide Synthases