L-arginine abolishes the hypothalamic serotonergic activation induced by central interleukin-1 beta administration to normal rats

• Autor(a) principal: Iuras, Anderson [UNIFESP]
• Data de Publicação: 2013
• Outros Autores: Telles, Monica Marques [UNIFESP], Andrade, Iracema Senna de [UNIFESP], Santos, Gianni Mara Silva dos [UNIFESP], Oyama, Lila Missae [UNIFESP], Nascimento, Claudia Maria da Penha Oller do [UNIFESP], Silveira, Vera Lucia Flor [UNIFESP], Ribeiro, Eliane Beraldi [UNIFESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• dARK ID: ark:/48912/001300001bpq7
• DOI: 10.1186/1742-2094-10-147
• Texto Completo: https://dx.doi.org/10.1186/1742-2094-10-147; https://repositorio.unifesp.br/handle/11600/37075
• topic: Brain microdialysis; Food intake; Nitric oxide; Serotonin ventromedial hypothalamus

IL-1 beta-induced anorexia may depend on interactions of the cytokine with neuropeptides and neurotransmitters of the central nervous system control of energy balance and serotonin is likely to be one catabolic mediator targeted by IL-1 beta. in the complex interplay involved in feeding modulation, nitric oxide has been ascribed a stimulatory action, which could be of significance in counteracting IL-1 beta effects.The present study aims to explore the participation of the nitric oxide and the serotonin systems on the central mechanisms induced by IL-1 beta and the relevance of their putative interactions to IL-1 beta hypophagia in normal rats. Serotonin levels were determined in microdialysates of the ventromedial hypothalamus after a single intracerebroventricular injection of 10 ng of IL-1 beta, with or without the pre-injection of 20 mu g of the nitric oxide precursor L-arginine. IL-1 beta significantly stimulated hypothalamic serotonin extracellular levels, with a peak variation of 130 +/-37% above baseline. IL-1 beta also reduced the 4-h and the 24-h food intakes (by 23% and 58%, respectively). the IL-1 beta-induced serotonergic activation was abolished by the pre-injection of L-arginine while the hypophagic effect was unaffected.The data showed that one central effect of IL-1 beta is serotonergic stimulation in the ventromedial hypothalamus, an action inhibited by nitric oxide activity. It is suggested that, although serotonin participates in IL-1 beta anorexia, other mechanisms recruited by IL-1 beta in normal rats are able to override the absence of the serotonergic hypophagic influence.