RESUMO A Adenosina desaminase (ADA) representa um ponto de controle crítico na regulação dos níveis de adenosina. A rutina, um flavonóide polifenólico presente em muitas plantas, foi testado para verificar a sua influência na atividade da ADA no soro, córtex cerebral, fígado rim e parâmetros bioquímicos em ratos diabéticos. Os animais foram divididos em quatro grupos cada grupo com 6 animais), tal como: controle; diabética (estreptozotocina 55 mg/kg); diabética + rutina (100 mg/kg/dia); diabético + glibenclamida (10 mg/kg/dia). Após 30 dias foram analisadas a atividade da ADA sérica e tecidual e parâmetros bioquímicos. A atividade de ADA no soro foi significativamente elevada no grupo diabético quando comparado ao grupo controle (p<0,01). O tratamento com Rutina preveniu o aumento na atividade da ADA nos ratos diabéticos, quando comparado com o grupo controle. Os resultados mostraram que a rutina reduziu a glicose, os níveis de LDL e as enzimas hepáticas, em comparação com o grupo controle. Estes resultados mostram que o aumento da atividade da ADA observado em ratos diabéticos pode ser um indicador importante da imuno-patogênese de perturbações hiperglicêmicas e sugerem que a Rutina é importante na regulação das atividades enzimáticas associadas com a resposta imunitária, hiperglicêmica e inflamatória no Diabetes mellitus.

ABSTRACT denosine deaminase (ADA) is a critical control point in the regulation of adenosine levels. This study aimed to investigate the effects of a polyphenolic flavonoid, rutin, on the activity of ADA in serum, the cerebral cortex, liver, kidney, and biochemical parameters in diabetic rats. The animals were divided into four groups (n=6) for the following treatments: control; diabetic (streptozotocin 55 mg/kg); diabetic with rutin (100 mg/kg/day); diabetic with glibenclamide (10 mg/kg/day). After 30 days, ADA activity and biochemical parameters were analyzed. The ADA activity in the serum was significantly elevated in the diabetic group compared to the control group (p<0.01). The treatment with rutin prevented the increase in ADA activity in the STZ-induced rats when compared to control group. Our data showed that rutin reduced glucose, LDL levels, and hepatic enzymes in comparison with the control group. These results demonstrate that the increase of ADA activity observed in diabetic rats may be an important indicator of the immunopathogenesis of hyperglycemic disorders and suggest that rutin is important for regulating the enzymatic activities associated with immune, hyperglycemic, and inflammatory response in diabetes mellitus.

A long-standing debate in the literature is whether attention can form two or more independent spatial foci in addition to the well-known unique spatial focus. There is evidence that voluntary visual attention divides in space. The possibility that this also occurs for automatic visual attention was investigated here. Thirty-six female volunteers were tested. In each trial, a prime stimulus was presented in the left or right visual hemifield. This stimulus was characterized by the blinking of a superior, middle or inferior ring, the blinking of all these rings, or the blinking of the superior and inferior rings. A target stimulus to which the volunteer should respond with the same side hand or a target stimulus to which she should not respond was presented 100 ms later in a primed location, a location between two primed locations or a location in the contralateral hemifield. Reaction time to the positive target stimulus in a primed location was consistently shorter than reaction time in the horizontally corresponding contralateral location. This attentional effect was significantly smaller or absent when the positive target stimulus appeared in the middle location after the double prime stimulus. These results suggest that automatic visual attention can focus on two separate locations simultaneously, to some extent sparing the region in between.