Dear Vahid Hajali,

You can go for ELISA to measure acetylcholine levels in brain and also many other samples like Cell culture supernatant, Urine, Serum, Plasma, Cell culture extracts, Other biological fluids, other tissue Extracts.

Here is the link for Abcam Choline/Acetylcholine Assay Kit (ab65345) go through it.

http://www.abcam.com/cholineacetylcholine-assay-kit-ab65345.html

Best of luck

Hi, you can use microdialysis and have "real-time" changes and there are a lot of publications already. Using a combination with MS or/and HPLC, you gonna to obtain absolute or relative (to baseline for example) changes in concentration even from very discreet regions (1mm^3). However, an access to equipment or investment required. Depends on accuracy level you need and possibilities. Also you can use HPLC/MS analysis of samples (biofluids of tissue) this is also quantitative and very accurate. Best regards.

Acetylcholine can be easily measured using an adequately equipped HPLC-ED system. These are few and far between but most large universities have one. Also depends on whether you want to measure extracellular ("released") acetylchoilne or acetylcholine levels (includes released and stored acetylcholine). Microdialysis would tell you about extracellular levels.

Thanks all, but i have heard that Ach in the brain samples is so sensitive and it would be degraded very quickly. Is it true? I have experience with collecting rat hippopotamus samples for molecular assays. is it as the same?