Lipoic acid effects on glutamate and taurine concentrations in rat hippocampus after pilocarpine-induced seizures / Efeitos do ácido lipóico nas concentrações de glutamato e taurina no hipocampo de ratos após convulsões induzidas por pilocarpina

Pilocarpine-induced seizures can be mediated by increases in oxidative stress and by cerebral amino acid changes. The present research suggests that antioxidant compounds may afford some level of neuroprotection against the neurotoxicity of seizures in cellular level. The objective of the present study was to evaluate the lipoic acid (LA) effects in glutamate and taurine contents in rat hippocampus after pilocarpine-induced seizures. Wistar rats were treated intraperitoneally (i.p.) with 0.9 percent saline (Control), pilocarpine (400 mg/kg, Pilocarpine), LA (10 mg/kg, LA), and the association of LA (10 mg/kg) plus pilocarpine (400 mg/kg), that was injected 30 min before of administration of LA (LA plus pilocarpine). Animals were observed during 24 h. The amino acid concentrations were measured using high-performance liquid chromatograph (HPLC). In pilocarpine group, it was observed a significant increase in glutamate content (37 percent) and a decrease in taurine level (18 percent) in rat hippocampus, when compared to control group. Antioxidant pretreatment significantly reduced the glutamate level (28 percent) and augmented taurine content (32 percent) in rat hippocampus, when compared to pilocarpine group. Our findings strongly support amino acid changes in hippocampus during seizures induced by pilocarpine, and suggest that glutamate-induced brain damage plays a crucial role in pathogenic consequences of seizures, and imply that strong protective effect could be achieved using lipoic acid through the release or decrease in metabolization rate of taurine amino acid during seizures.

As convulsões induzidas pela pilocarpina podem ser mediadas através do aumento do estresse oxidativo cerebral e das alterações na concentração dos aminoácidos. O presente estudo sugere que compostos antioxidantes podem produzir neuroproteção contra a neurotoxicidade em nível celular causada pelas convulsões. O objetivo deste estudo foi avaliar os efeitos do ácido lipóico (AL) no conteúdo de glutamato e taurina no hipocampo de ratos durante convulsões induzidas por pilocarpina. Ratos Wistar foram tratados por via intraperitoneal com solução salina 0,9 por cento (controle), pilocarpina (400 mg/kg, pilocarpina), AL (10 mg/kg) e com a associação de AL (10 mg/kg); 30 min após com pilocarpina (400 mg/kg), que foi injetada 30 min após a administração de AL (AL + pilocarpina). Os animais foram observados durante 24 horas. As concentrações de aminoácidos foram determinadas por HPLC. No hipocampo dos ratos do grupo pilocarpina foi observado um aumento significativo de 37 por cento na concentração de glutamato e uma diminuição de 18 por cento no nível de taurina, quando comparado ao grupo controle. O pré-tratamento com o antioxidante reduziu significativamente o nível de glutamato em 28 por cento e aumentou em 32 por cento os níveis de taurina no hipocampo dos ratos, quando comparado ao grupo pilocarpina. Nossos resultados sugerem que ocorrem alterações na concentração dos aminoácidos no hipocampo de ratos durante as convulsões induzidas por pilocarpina, e que o glutamato pode desempenhar um papel crucial na fisiopatologia das convulsões, e que o efeito protetor poderia ser alcançado com pré-tratamento com ácido lipóico, provavelmente pelo aumento da liberação ou redução da taxa de metabolização dos aminoácidos durante as convulsões.

Choline acetyltransferase and acetylcholinesterase activities are reduced in rat striatum and frontal cortex after pilocarpine-induced seizures.

In the present study we investigated the alterations on choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) activities in rat striatum and frontal cortex caused by pilocarpine-induced seizures. Wistar rats were treated with 0.9% saline (i.p., control group), with the association of 0.9% saline (i.p.) plus pilocarpine (400mg/kg, i.p.), 30 min before of administration of saline (pilocarpine group). After the treatments all groups were observed for 1h. The ChAT and AChE activities were measured using spectrophotometric methods and the results compared to values obtained from saline-treated animals. In pilocarpine group was observed a significantly decreases in ChAT and AChE activities in striatum and frontal cortex of adult rats, when compared to control group. Results showed that during acute phase of seizures striatal and frontal cortex ChAT and AChE activities are diminished. Our findings suggest that seizures caused cognitive dysfunction and decreases of ChAT and AChE activities that might be related, at least in part, to the neurological problems presented by epileptic patients.

Prevalência de tuberculose urogenital no estado do Ceará no ano de 2003 / Prevalence urogenital tuberculosis in Ceará during 2003 year

No período de janeiro à dezembro de 2003 foram enviados ao Laboratório Central do estado do Ceará ( LACEN-Ce), 1.028 espécimes clínicos (urina), coletados de 112 pacientes com suspeita de tuberculose urogenital, onde 79 (7,7) destes espécimes apresentaram baciloscopia e cultura positiva para o complexo Mycobacterium tuberculosis. Dos 112 pacientes apenas 40 (35,7)...