Ethidium bromide inhibits rat brain acetylcholinesterase activity in vitro.
Ethidium bromide (EtBr), a fluorescent dark red compound and stain for double-stranded DNA and RNA was used to study acetylcholinesterase (AChE) activity in vitro together with kinetic parameters of this enzyme in the striatum (ST), hippocampus (HP), cerebral cortex (CC) and cerebellum (CB) of adult rats. AChE activity in vitro in the ST, HP, CC and CB was significantly reduced (p<0.05) in the presence of EtBr at concentrations of 0.00625, 0.0125, 0.025, 0.05 and 0.1 mM. For the analysis of the kinetic three concentrations of EtBr were tested (0.00625, 0.025 and 0.1 mM). An uncompetitive inhibition type was observed in the ST, HP and CC, whereas in the CB the inhibition type was mixed. These data indicate that EtBr should be considered a strong inhibitor of AChE activity demonstrating that there is an interaction between this compound and the cholinergic system.
Mazzanti
Cinthia M
CM
Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcellos, 2600-Anexo 90035-003, Porto Alegre, RS, Brazil.
Spanevello
Roselia M
RM
Obregon
Adriana
A
Pereira
Luciane B
LB
Streher
Cristiane A
CA
Ahmed
Mushtaq
M
Mazzanti
Alexandre
A
Graça
Dominguita L
DL
Morsch
Vera M
VM
Schetinger
Maria Rosa C
MR
D000110:Acetylcholinesterase / Q000737:chemistry* / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000201:enzymology*; D002384:Catalysis / Q000187:drug effects; D002531:Cerebellum / Q000201:enzymology; D002540:Cerebral Cortex / Q000201:enzymology; D002800:Cholinesterase Inhibitors / Q000737:chemistry* / Q000494:pharmacology; D003342:Corpus Striatum / Q000201:enzymology; D004305:Dose-Response Relationship, Drug; D004996:Ethidium / Q000737:chemistry* / Q000494:pharmacology; D006624:Hippocampus / Q000201:enzymology; D007700:Kinetics; D008297:Male; D051381:Rats; D017208:Rats, Wistar
D002800:Cholinesterase Inhibitors; D000110:Acetylcholinesterase; D004996:Ethidium