ACETYLCHOLINESTERASE, IN THE OLFACTORY OR GAN OF THE COMMON CARP CYPRINUS-CARPIO (TELEOST, CYPRINIDAE) - CHARACTERIZATION OF MOLECULAR-FORMS IN-VITRO AND IN-VIVO INHIBITION BY CARBOFURAN

The use of pesticides in agriculture and in insect control has been cr eating a potential danger to aquatic life and human health. Acetylchol inesterase, an enzyme regulating nerve-impulse transmission, is report ed to be inhibited by carbamates and organophosphates in many living s ystems including aquatic organisms. AChE is also present in the entire olfactory organ of the common carp Cyprinus carpio. The native molecu lar forms of AChE present in olfactory organ have been characterized b y sedimentation analysis in sucrose gradients. AChE exists as gobular and asymmetric forms. The reduction of olfactory organ AChE activity i s already perceptible at sublethal concentrations of carbofuran. The r esults show an inhibition of olfactory organ AChE ranging from 33,4% t o 49,3% after 48 hours. This makes the AChE activity a potential bioch emical indicator of toxic stress in fishes and a sensitive test for th e presence of carbamates and organophosphates in water.