Studies on the Cholinesterase Activity of the Body Wall of the Annelid.

The cholinesterase activities of homogenates of the body wall in earthworms and nereids were measured by Ammon's method using Waburg's manometric technique. Substrates used in this experiment were acetylcholine (Ach), benzoylcholine (Bch), acety-β-methylcholine (MCh) and butyrylcholine (BuCh). The results were as follws : 1. The rate of hydrolysis of Ach was markedly higher in earthworm tissue thanin nereid tissue. 2. The rate of hydrolysis of Ach was markedly higher in earthworm tissur tha in nereid tissue. 2. The rate of hydrolysis of MCh was greater than that of BCh in both the earthworm and dereid tissues. The average MCh/BCh ratio of nereid tissue was greater than that of earthworm tissue. 3. The rate of hydrolysis of BuCh was small in both the earthworm and nereid tissues. In view of the results obtrained it semms reasonable to conclude that the tissues of both earthworms and nereids have activity of true-cholinesterase than pseudo-cholinestrease.