QUANTITATIVE DISTRIBUTIONS OF DIFFERENT CHOLINESTERASES AND INHIBITION OF ACETYLCHOLINESTERASE BY METIDATHION AND PARAQUAT IN ALIMENTARY CANAL OF COMMON CARP

1. The cholinesterases play an important role in the innervation of or gans. The ratio of solubilized to membrane bound cholinesterase and th e quantitative distributions of acetylcholinesterase and butyrylcholin esterase were measured in different segments of the gut of carp (Cypri nus carpio) connected with different types of nerve-muscle synapses in different parts of the alimentary tract. 2. The inhibition of acetylc holinesterase (EC 3.1.1.7.) by the herbicide paraquat and the insectic ide metidathion was measured in different parts of the gut of carp. 3. Metidathion and paraquat significantly decreased the activity of acet ylcholinesterase in different segments of the alimentary tract of comm on carp, in a concentration dependent manner. (C) 1997 Elsevier Scienc e Inc.