RESUMO
Cyanide is a potential suicidal, homicidal and chemical warfare agent. It produces histotoxic hypoxia following inhibition of cytochrome c oxidase, a terminal respiratory chain enzyme. The profound metabolic changes lead to neurotoxicity including alterations in the levels of neurotransmitters. The present study addressed the effect of acute exposure of lethal and sub-lethal doses of potassium cyanide (KCN; 0.75 or 2.0 LD50; po) on the levels of neurotransmitters in discrete brain regions of rats and its response to treatment with a-ketoglutarate (-KG; 0.5 g/kg; po; -10 min) alone or with sodium thiosulphate (STS; 1.0 g/kg; ip; -15 min). KCN significantly decreased norepinephrine, dopamine and 5-hydroxytryptamine levels in different brain regions which were resolved by a-KG and/or STS. Corpus striatum and hippocampus were more sensitive as compared to cerebral cortex and hypothalamus. -KG, a potential cyanide antidote alone or with STS showed neuroprotective effects against cyanide.
RESUMO
Neurite outgrowth is essential for the communication of the nervous system. The rat Pheochromocytoma (PC12) cells are commonly used in the neuronal cell study. It is well known that exogenous stimuli such as Nerve Growth Factor (NGF) induce neurite outgrowth. In the present study it has been investigated whether or not the conditioned medium from human neuroblastoma cell line (IMR-32) and human glioblastoma cell line (U87MG) may augment neurite outgrowth in PC12 cells. PC12 were cultured with and without conditioned media of IMR-32 and U87MG. The result showed that both the conditioned media induce neurite outgrowth within 48 hr and stops further proliferation of PC12 cells. However no outgrowth was noted in PC12 cells incubated without conditioned medium. In conclusion, it is shown that both the conditioned media (IMR-32 and U87MG) have the potential to induce the neurite outgrowth in the PC12 cells.