Electrocorticographic patterns dominated by low-frequency waves in camphor-induced seizures.

Camphor is an aromatic terpene compound found in the essential oils of many plants, which has been used for centuries as a herbal medicine, especially in children. However, many studies have shown that camphor may have major side effects, including neurological manifestation, such as seizures. In the present study, we investigated the electrocorticographic patterns of seizures induced by camphor in male adult Wistar rats. Each rat received 400 mg/kg (i.p.) of camphor prior to monitoring by electrocorticography. The application of camphor resulted a rapid evolution to seizure and marked changes in the electrocorticographic readings, which presented characteristics of epileptiform activity, with an increase in the total power wave. The decomposition of the cerebral waves revealed an increase in the delta and theta waves. The analysis of the camphor traces revealed severe ictal activity marked by an increase in the polyspike wave. Our data thus indicate that camphor may cause seizures, leading to tonic-clonic seizures. Clearly, further studies are necessary to better elucidate the mechanisms through which camphor acts on the brain, and to propose potential treatments with anticonvulsant drugs that are effective for the control of the seizures.

Cunaniol-elicited seizures: Behavior characterization and electroencephalographic analyses.

This study aimed at describing the characteristics and properties of seizures induced by cunaniol, a polyacetylenic alcohol isolated from the Clibadium genus, which is ubiquitous in the Amazon biodiversity and its potential use as a convulsant model. Wistar rat behavior was assessed upon cunaniol administration and animals were evaluated for neural activity through electroencephalographic records whereby epidural electrodes were positioned over the motor cortex under cunaniol-elicited seizures and seizure's control using three anticonvulsant agents, namely phenytoin, phenobarbital and diazepam. Cunaniol-induced seizures displayed a cyclic development of electrocorticographic seizures, presenting interictal-like spike and ictal period, which correlates to the behavioral observations and is in line with acute seizures induced by pentylenetetrazole. Cunaniol-elicited seizures were intractable by phenytoin treatment and controlled under the GABAergic activities of phenobarbital and diazepam. The results indicate that the cunaniol-induced changes show characteristics of seizure activity, making this plant compound a suitable animal convulsant model for seizure-related studies that could be used to assist in the development of novel anticonvulsant agents.

Effects of L-Argine on in vivo concentration of metabolites in the blood and in myocutaneous flaps with surgical scars, in wistar rats

The epithelialization, contraction and deposition of connective tissue are the mechanisms by which wounds heal Studies have shown that L-Arginine favors wound hearing by increasing the synthesis of collagen. This paper aimed at studying the effects of L-Arginine supplementation on in vivo concentrations of glucose, pyruvate, lactate and ketone bodies in the blood and in myocutaneous flaps undergoing hearing.Forty-four white male Wistar rats were distributed in two groups: (G-l/Control) and (G-2/Expeiiment). The G-1 animals received iso-proteic casein supplementation and the G-2 group received L-Arginine by gavage daily. Beth groups were submitted to pediculated and dorsal myocutaneous flaps. In the post-operative period, each group was subdivided into three subgroups and, after 7, 14 and 30 days, blood and scar tissue samples were collected for analyses of enzymes. The drop in blood concentrations of pyruvate, lactate and ketone bodies on the 14th day suggests higher utilization of these metabolites in peripheral tissues by a possible anabolic action of L-Arginine. The increase of tissue concentrations of ketone bodies in the myocutaneous flap on the 30th post-operative day in animals treated with L-Arginine food supplementation indicates a probable increase in the utilization of these metabolites by tissues under scarring. The results suggest that L-Arginine supplementation has an effect on serum concentrations of substrates and on skin and muscle scarring.

Efeitos biológicos do mercúrio e seus derivados em seres humanos: uma revisão bibliográfica / Biological effects of mercury and its compounds in human being: a mini-review

Introdução: O mercúrio e seus derivados são considerados poluentes ambientais originados de várias fontes. A preocupação maior a respeito da poluição mercurial é decorrente dos efeitos à saúde relacionados à exposição ao mercúrio metilado (metilmercúrio) encontrado na água e alimentos aquáticos. O sistema nervoso central é o alvo principal do metilmercúrio. Este metal também é reconhecidamente um agente teratogênico. No entanto, seus efeitos genotóxicos(ação no DNA) são de difícil interpretação e contraditórios. Objetivo: Este trabalho tem por objetivo realizar uma revisão bibliográfica enfocando os efeitos biológicos deste metal e seus derivados em humanos, visando uma melhor compreensão sobre seu variado modo de ação na saúde dos indivíduos. Método: Foi realizado um levantamento bibliográfico com trabalhos pertinentes, enfatizando-se a produção mais recente a respeito do assunto. Considerações Finais: Os efeitos biológicos do mercúrio e seus derivados são extremamentes variados, apresentado, no entanto, consequências suficientemente graves que justificam a realização cada vez maior de estudos suplementares, que servirão como modelos para manter a integridade da saúde de pessoas expostas