PUBLICATION
Exposure to Hg(2+) and Pb(2+) changes NTPDase and ecto-5'-nucleotidase activities in central nervous system of zebrafish (Danio rerio)
- Authors
- Senger, M.R., Rico, E.P., de Bem Arizi, M., Frazzon, A.P., Dias, R.D., Bogo, M.R., and Bonan, C.D.
- ID
- ZDB-PUB-060906-3
- Date
- 2006
- Source
- Toxicology 226(2-3): 229-237 (Journal)
- Registered Authors
- Bonan, Carla Denise
- Keywords
- NTPDase, Ecto-52-nucleotidase, Heavy metals, Mercury, Lead, Zebrafish
- MeSH Terms
-
- 5'-Nucleotidase/biosynthesis
- 5'-Nucleotidase/metabolism*
- Adenosine Diphosphate/metabolism
- Adenosine Triphosphatases/metabolism*
- Adenosine Triphosphate/metabolism
- Animals
- Brain/enzymology
- Brain Chemistry/drug effects
- Central Nervous System/drug effects*
- Central Nervous System/enzymology*
- In Vitro Techniques
- Lead/toxicity*
- Membranes/drug effects
- Membranes/metabolism
- Mercury/toxicity*
- Nerve Tissue Proteins/analysis
- Nerve Tissue Proteins/biosynthesis
- Receptors, Purinergic/drug effects
- Reverse Transcriptase Polymerase Chain Reaction
- Zebrafish
- PubMed
- 16930798 Full text @ Toxicology
Citation
Senger, M.R., Rico, E.P., de Bem Arizi, M., Frazzon, A.P., Dias, R.D., Bogo, M.R., and Bonan, C.D. (2006) Exposure to Hg(2+) and Pb(2+) changes NTPDase and ecto-5'-nucleotidase activities in central nervous system of zebrafish (Danio rerio). Toxicology. 226(2-3):229-237.
Abstract
Neurotransmission can be affected by exposure to heavy metals, such as mercury and lead. ATP is a signaling molecule that can be metabolized by a group of enzymes called ecto-nucleotidases. Here we investigated the effects of mercury chloride (HgCl(2)) and lead acetate (Pb(CH(3)COO)(2)) on NTPDase (nucleoside triphosphate diphosphohydrolase) and ecto-5'-nucleotidase activities in zebrafish brain membranes. In vitro exposure to HgCl(2) decreased ATP and ADP hydrolysis in an uncompetitive mechanism and AMP hydrolysis in a non-competitive manner. Pb(CH(3)COO)(2) inhibited ATP hydrolysis in an uncompetitive manner, but not ADP and AMP hydrolysis. In vivo exposure of zebrafish to HgCl(2) or Pb(CH(3)COO)(2) (20mug/L, during 24, 96h and 30 days) caused differential effects on nucleotide hydrolysis. HgCl(2), during 96h, inhibited the hydrolysis of ATP, ADP and AMP. After 30 days of exposure to HgCl(2), ATP hydrolysis returned to the control levels, ADP hydrolysis was strongly increased and AMP hydrolysis remained inhibited. Exposure to Pb(CH(3)COO)(2) during 96h caused a significant decrease only on ATP hydrolysis. After 30 days, Pb(CH(3)COO)(2) promoted the inhibition of ATP, ADP and AMP hydrolysis. Semi-quantitative RT-PCR analysis showed no changes in the expression of NTPDase1 and 5'-nucleotidase, following 30 days of exposure to both metals. This study demonstrated that Hg(2+) and Pb(2+) affect the ecto-nucleotidase activities, an important enzymatic pathway for the control of purinergic signaling.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping