Page 437 - The Toxicology of Fishes

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Toxic Responses of the Fish Nervous System

Steven P. Bradbury, Richard W. Carlson, Tala R. Henry,
Stephanie Padilla, and John Cowden

CONTENTS
Introduction............................................................................................................................................418
Overview of Fish Nervous System Development, Structure, and Function.........................................418
Development of the Fish Nervous System ..................................................................................418
Central Nervous System Anatomy...............................................................................................420
Prosencephalon ...................................................................................................................421
Mesencephalon ...................................................................................................................421
Rhombenchephalon.............................................................................................................422
Spinal Cord.........................................................................................................................422
Peripheral Nervous System Anatomy and Function: The Autonomic Nervous System ............ 422
Sensory Organ Systems................................................................................................................423
Basic Mechanisms of Neurotoxicity .....................................................................................................425
Manifestations of Neurotoxicity in Fish ...............................................................................................426
Structural Manifestations of Neurotoxicity in Fish.....................................................................426
Physiological Manifestations of Neurotoxicity in Fish...............................................................427
Electrophysiology ...............................................................................................................427
Respiratory–Cardiovascular................................................................................................427
Behavioral...........................................................................................................................428
Examples of Major Classes of Neurotoxicants.....................................................................................429
Narcotics.......................................................................................................................................429
Mechanisms of Narcotic Neurotoxicity .............................................................................429
Manifestations of Narcotic Neurotoxicity in Fish .............................................................429
Cholinesterase Inhibitors..............................................................................................................431
Mechanisms of Cholinesterase Inhibitor Neurotoxicity ....................................................432
Manifestations of Cholinesterase Inhibitor Neurotoxicity in Fish....................................433
Pyrethroid Insecticides.................................................................................................................434
Mechanisms of Pyrethroid Neurotoxicity..........................................................................435
Manifestations of Pyrethroid Neurotoxicity in Fish..........................................................436
Organochlorine Insecticides.........................................................................................................437
Mechanisms of Organochlorine Insecticide Neurotoxicity ...............................................437
Manifestations of Organochlorine Insecticide Neurotoxicity in Fish ............................... 439
Ethanol..........................................................................................................................................439
Mechanisms of Ethanol Neurotoxicity...............................................................................439
Manifestations of Ethanol Neurotoxicity in Fish...............................................................439
Metals ...........................................................................................................................................440
Mechanisms of Metal Neurotoxicity..................................................................................440
Manifestations of Metal Neurotoxicity in Fish..................................................................442
Neurotoxins ..................................................................................................................................443
Mechanisms of Neurotoxin Toxicity..................................................................................443
Manifestations of Neurotoxin Toxicity in Fish..................................................................444

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