Methodische versuche zur analytik von prostaglandinen und ermittlung ihrer syntheseraten am beispiel bos - artiger tumore

Abstract

To determine the metabolic fate of prostaglandins quantitively and qualitivcly as well, various normal and pathologically altered tissues were estimated by different methods up till now. RIA, HPLC, GC/MS # 1 / and Bioassay. Using RTLC the separation of C-labeled prostaglandins metabolized from 1 -^ C -A A was estimated. The advantage of ^ C - labeling is the high recovery (10-3CSO in contrast to "H-labeling. The separation of the prostaglandin dérivâtes formed was done on thin layer plates; the identification of the different prostaglandins such as PGI 2 » PGD? , P G F 2 , P G F ^ , was performed by comparison with unlabeled prostaglandins, being applied on the same plates. For the quantitative determination a standard curve was done for each prostaglandin. Using RTLC, having the advantage to detect small amounts of prostaglandins, the dependence of the prostaglandin metabolism from the incubationmedium, as well as on the methodology the incubation was done, was investigated. Therefore, media of different pH were used, and the inhibition of prostaglandin synthesis was estimated by the addition of enzymatic inhibitors, like cyclooxygenase inhibitor, prostacyclin - synthetase inhibitor and the inactivation of the specific enzymes by heating and acidifying was investigated. Normal tissue samples which have been histologically separated into mucosa and muscle cells and cancer tissue ( especially of the colon and the ovarium) were investigated in order to examine whether there are differences in the prostaglandin synthesis profile.