A COMPARATIVE STUDY OF ACETYLCHOLINESTERASE PRESENT IN THE WHITE AND GREY MATTER OF PIG BRAIN

Publisher Summary The brain is a rich source of acetylcholinesterase (acetylcholine hydrolase, EC 3.1.1.7.), although the distribution throughout the tissue is very uneven. This chapter discusses a comparative study of acetylcholinesterase present in the white and grey matter of pig brain. In this study, the purification of the enzyme was carried out on an affinity column of agaraose. The criterion of solubility was taken as the enzyme remaining in the supernatant after centrifugation at 100,000 g for 1 h. The homogenization of the white or grey matter of brain in 30 mM sodium phosphate buffer (pH 7.0) followed by centrifugation yielded a supernatant fraction and a pellet. Triton X-100 was not very effective at solubilizing AChE from the white matter of brain because only 33% of the activity could be brought into solution and this is only 18% more than the naturally soluble enzyme. In contrast to this, Triton X-100 solubilized up to 71% of the activity present in the grey matter. This suggests that AChE is more firmly bound to the membrane in the white matter than in the grey matter of the pig brain.