Effect of subchronic treatment with mercury chloride on NTPDase, 5'-nucleotidase and acetylcholinesterase from cerebral cortex of rats.
The aim of the present investigation was to evaluate the effect of a subchronic treatment (30 days/30 doses) with subcutaneous injections (0.1 mg/kg) of HgCl2 on NTPDase (E.C. 3.6.1.5), 5'-nucleotidase (E.C 3.1.3.5) and acetylcholinesterase (AChE, E.C. 3.1.1.7) activities in brain from adult rats. NTPDase and 5'-nucleotidase were measured in cortical synaptosomal fraction and AChE was measured in the homogenate of cerebral cortex and hippocampus. After the subchronic treatment (30 days), NTPDase activity was enhanced approximately 35% (p < 0.05) with ATP and ADP as substrates and no difference was observed in 5'-nucleotidase activity (AMP hydrolysis). In addition, AChE activity was enhanced in the cerebral cortex (22%, p < 0.05) and hippocampus (26%, p < 0.05) after the subchronic treatment. Mercury deposited in brain was measured by cold vapor (atomic absorption spectrometry) and no difference between the control and the subchronically treated group was observed. Here we showed for the first time that exposure to low levels of Hg2+, which resembles occupational exposure to low levels of mercury, caused a marked increase in NTPDase and AChE activities. The relationship of these alterations with the neurotoxicity of inorganic mercury deserves further studies.
Moretto
Maria Beatriz
MB
Departamento de Análises Clínicas, Centro de Ciências da Saúde, Universidade Federal de Santa Maria, Santa Maria, Brazil.
Lermen
Carine Luísa
CL
Morsch
Vera Maria
VM
Bohrer
Denise
D
Ineu
Rafael Porto
RP
da Silva
Adriane Cismoski
AC
Balz
Daniela
D
Schetinger
María Rosa Chitolina
MR
D015720:5'-Nucleotidase / Q000378:metabolism*; D000110:Acetylcholinesterase / Q000378:metabolism*; D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D000891:Anti-Infective Agents, Local / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000187:drug effects* / Q000201:enzymology*; D004789:Enzyme Activation; D006624:Hippocampus / Q000187:drug effects / Q000201:enzymology; D006801:Humans; D008297:Male; D008627:Mercuric Chloride / Q000737:chemistry / Q000494:pharmacology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013347:Subcellular Fractions / Q000737:chemistry / Q000378:metabolism; D013574:Synaptosomes / Q000201:enzymology
D000891:Anti-Infective Agents, Local; D008627:Mercuric Chloride; D000110:Acetylcholinesterase; D015720:5'-Nucleotidase; D000251:Adenosine Triphosphatases