RESUMO
Organophosphate (OP) pesticides, monocrotophos (MCP), dichlorvos (DDVP) and phosphamidon significantly inhibit both MAO-A and MAO-B activities in rat brain mitochondria. The inhibition of MAO-A by MCP is reversible whereas the inhibition by DDVP and phosphamidon is irreversible. MAO-B is inhibited irreversibly by all these organophosphates suggesting that the mechanism of action of OP pesticides is through phosphorylation of serine residue present in active centre of MAO.
Assuntos
Animais , Benzilaminas/metabolismo , Encéfalo/enzimologia , Inseticidas/metabolismo , Masculino , Mitocôndrias/enzimologia , Monoaminoxidase/metabolismo , Compostos Organofosforados , Oxirredução , Ratos , Ratos Wistar , Serotonina/metabolismoRESUMO
The psychoactive drugs imipramine, chlorpromazine and lithium chloride inhibit tryptamine tetrazolium reductase activity in vitro by 68, 60 and 33% respectively at a concentration of 1 x 10(-3) M while amphetamine negligibly inhibits the enzyme activity. No change in enzyme activity is observed in vivo.