[Determination of cholinesterase activity in Fasciola hepatica homogenates].

The cholinesterase activity in Fasciola hepatica homogenates was studied through biological techniques. Results depict that the contractile stimulating action of a constant acetylcholine dose on the isolated rat duodenum is withdrawn when the agent is previously incubated at 37 degrees C during 30 minutes with different dilutions (20%, 40% and 80%) of Fasciola hepatica homogenates. The action is recovered when an anticholinesterase, as neostigmine is previously added to the homogenate. Since these effects are similar to those obtained when different dilutions of human blood serum with a high content of cholinesterase are led to act upon the acetylcholine dose, it is concluded that the acetylcholine inactivation induced by Fasciola hepatica homogenates results from the existence of such enzyme within this parasite.