Clinical expression of organophosphate-induced delayed polyneuropathy in rats.

Abstract

Single doses of certain organophosphates (OP), such as dibutyl-2,2-dichlorovinyl phosphate (DBDCVP) cause organophosphate-induced delayed polyneuropathy (OPIDP) in hens. Clinical effects correlate with inhibition of neuropathy target esterase (NTE) which is considered the target for this toxicity. Pre-treatment with non-neuropathic NTE inhibitors, such as phenylmethanesulfonyl fluoride (PMSF), protects from OPIDP. However, when given after OPs, these compounds promote OPIDP. Chicks are relatively resistant to OPIDP despite high NTE inhibition. It has also always been reported that rats represent a species which is resistant to OPIDP and that they might develop morphological but not clinical signs of OPIDP. We report here that clinical OPIDP can be produced in 3.5- and 6-month-old rats by DBDCVP (5 mg/kg s.c.) and that it correlates with high (> 90%) NTE inhibition. When PMSF (120 mg/kg s.c. x 2) was given after DBDCVP, OPIDP was promoted. Pretreatment with PMSF protected from OPIDP. We conclude that resistance to OPIDP in the rat is age-related, as it is in the hen.

• Authors: A Moretto, E Capodicasa, M Lotti
• Journal: Toxicology letters (Toxicol Lett) Vol. 63 Issue 1 Pg. 97-102 (Oct 1992) ISSN: 0378-4274 [Print] Netherlands
• PMID: 1412529 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• di-n-butyl-2,2-dichlorovinyl phosphate
• Dichlorvos
• Carboxylic Ester Hydrolases
• neurotoxic esterase
• Acetylcholinesterase

Topics

• Acetylcholinesterase (metabolism)
• Aging (metabolism)
• Animals
• Carboxylic Ester Hydrolases (antagonists & inhibitors, metabolism)
• Dichlorvos (analogs & derivatives, toxicity)
• Injections, Subcutaneous
• Male
• Motor Activity (drug effects)
• Rats
• Rats, Wistar