Acetyicholinesterase and Choline Acetyltransferase in Ram Spermatozoa

Abstract

Ram spermatozoa were investigated for the occurrence of acetylcholinesterase (AChE) and choline acetyltransferase (ChAc). It has been found that ram spermatozoa have an AChE activity with a V_max of 6 nmol acetylthiocholine hydrolysed/min/mg protein and a K_m of 2 x 10^-5 M. This enzyme showed substrate inhibition at acetylthiocholine concentrations greater than 10 mM and had a temperature optimum between 28°C and 37°C. The AChE was inhibited by eserine salicylate (10 µM), but was not affected by decamethonium ( 10 µM) or d-tubocurarine (1 mM).