Bovine chromaffin cell cultures as model to study organophosporus neurotoxicity.

Abstract

Based on the high level of phenyl valerate esterase activities, and in particular of neuropathy target esterase (NTE) found in bovine adrenal medulla, chromaffin cells culture have been proposed as an alternative model for the study of organophosphorus neurotoxicity. Organophosphorus-induced polyneuropathy is a syndrome related to the inhibition and further modification by organophosphorus compounds of NTE (a protein that displays phenyl valerate esterase activity resistant to mipafox and sensitive to paraoxon). Total phenyl valerate esterase activities found in homogenate, particulate and soluble fractions of bovine adrenal medulla were 5200+/-35, 5000+/-280 and 1700+/-260 mU/g tissue, respectively. Cultured chromaffin cells displayed a total hydrolysing activity of 41+/-5 mU/10(6) cells. Homogenates of bovine adrenal medulla displayed only about 6% of activity sensitive to paraoxon. Most of the phenyl valerate esterase activity inhibited by mipafox (a neuropathy inducing compound) was found in particulate fraction. Cultured chromaffin cells displayed kinetics of inhibition by mipafox similar to the kinetics displayed by homogenates of bovine adrenal medulla. We conclude that NTE could be assayed in this system by only using one inhibitor (mipafox) instead of two (paraoxon and mipafox). Also, the proposal is supported of using chromaffin cells as in vitro model for the study of the role of NTE and related esterases in organophosphorus-induced polyneuropathy.

• Authors: E Quesada, M A Sogorb, E Vilanova, V Carrera
• Journal: Toxicology letters (Toxicol Lett) Vol. 151 Issue 1 Pg. 163-70 (Jun 15 2004) ISSN: 0378-4274 [Print] Netherlands
• PMID: 15177651 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Enzyme Inhibitors
• Organophosphorus Compounds
• Isoflurophate
• mipafox
• Carboxylic Ester Hydrolases
• neurotoxic esterase
• Paraoxon

Topics

• Adrenal Medulla (drug effects, enzymology, metabolism)
• Animals
• Carboxylic Ester Hydrolases (antagonists & inhibitors, metabolism)
• Cattle
• Chromaffin Cells (drug effects, enzymology, metabolism)
• Enzyme Inhibitors (pharmacokinetics)
• Isoflurophate (analogs & derivatives, pharmacokinetics, toxicity)
• Neurotoxicity Syndromes (etiology)
• Organophosphorus Compounds (pharmacokinetics, toxicity)
• Paraoxon (pharmacokinetics, toxicity)
• Toxicity Tests (methods)