Tissue-specific inhibition and recovery of esterase activities in Lumbricus terrestris experimentally exposed to chlorpyrifos.
Comp Biochem Physiol C Toxicol Pharmacol
; 151(3): 351-9, 2010 Apr.
Article
em En
| MEDLINE
| ID: mdl-20045489
Exposure and effect assessment of organophosphate (OP) pesticides generally involves the use of cholinesterase (ChE) inhibition. In earthworm, this enzyme activity is often measured in homogenates from the whole organism. Here we examine the tissue-specific response of ChE and carboxylesterase (CE) activities in Lumbricus terrestris experimentally exposed to chlorpyrifos-spiked field soils. Esterases were measured in different gut segments and in the seminal vesicles of earthworms following acute exposure (2 d) to the OP and during 35d of a recovery period. We found that inhibition of both esterase activities was dependent on the tissue. Cholinesterase activity decreased in the pharynx, crop, foregut and seminal vesicles in a concentration-dependent way, whereas CE activity (4-nitrophenyl valerate) was strongly inhibited in these tissues. Gizzard CE activity was not inhibited by the OP, even an increase of enzyme activity was evident during the recovery period. These results suggest that both esterases should be determined jointly in selected tissues of earthworms. Moreover, the high levels of gut CE activity and its inhibition and recovery dynamic following OP exposure suggest that this esterase could play an important role as an enzymatic barrier against OP uptake from the ingested contaminated soil.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oligoquetos
/
Inibidores da Colinesterase
/
Clorpirifos
/
Inseticidas
Limite:
Animals
Idioma:
En
Revista:
Comp Biochem Physiol C Toxicol Pharmacol
Assunto da revista:
FARMACOLOGIA
/
TOXICOLOGIA
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Chile
País de publicação:
Estados Unidos