抄録
We attributed the altered contractile properties of vascular and non-vascular muscle strips in Tris containing medium to experimental variables such as sodium concentration and pH change. Imidazole is also used in various biomedical experiments. Effects of imidazole on contractile response to KCl as well as on the levels of phosphate creatine (PCr) and ATP in taenia coli isolated from guinea-pig were investigated. Methods: The cleaned preparations were placed in a chamber containing bicarbonate buffer (BB) gassed with 95% O2-5% CO2, or imidazol buffer (IB) gassed with 100% O2 at 37±0.5oC. Isometric tension was recorded via computer-based analysis using Mac-Lab. The levels of PCr and ATP in taenia coli were measured by the luciferin-luciferae method. Results: The level of PCr was gradually decreased after switching the buffer from BB to IB, and it was nearly exhausted 30 min after the exposure to IB. This alteration of the level of PCr was recovered by putting back the preparation to the BB. On the other hand, the ATP level and KCl-induced contraction in IB were not significantly different from those in BB. Effects of Tris buffer exposure were similar to those of IB exposure. Results may be related to an alteration of creatine kinase activity in the taenia coli. [J Physiol Sci. 2008;58 Suppl:S68]
