RESUMO
Neural involvement plays a role in the genesis of the peripheral inflammatory process that contributes to the irradiation intestinal disorders. However, little is known about the role of vagus nerve in modulating inflammatory process in rat. Here, we have shown that the NF-kappaB activation was consistent with the acute overexpression of pro-inflammatory cytokines (IL- 1beta, TNF-alpha, IL-6) at 3, 6, and 12 h induced by whole-body irradiation (8 Gy). Subdiaphragmatic vagotomy reduced NF-kappaB activation and cytokine transcription in the early period post-irradiation. In contrast, vagotomy amplified overexpression of irradiation-induced anti-cytokines (IL-10, IL-1Ra) and of receptors involved in anti-inflammatory effects (IL- 1RII, TNFRII). These results show that the vagus nerve is a pro-inflammatory pathway in early irradiation-induced intestinal inflammation.
Assuntos
Citocinas/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos da radiação , Íleo/efeitos da radiação , Vagotomia Troncular/métodos , Irradiação Corporal Total/métodos , Animais , Apoptose/fisiologia , Apoptose/efeitos da radiação , Citocinas/genética , Ensaio de Imunoadsorção Enzimática/métodos , Masculino , NF-kappa B/metabolismo , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Receptores de Citocinas/genética , Receptores de Citocinas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de TempoRESUMO
Organophosphonate (OP) nerve agents, such as soman, are potent irreversible inhibitors of central and peripheral acetylcholinesterases (AChEs). Pre-treatment of OP poisoning relies on the subchronic administration of a reversible AChE inhibitor. In the present limited study, the protective effects against soman toxicity of such compounds, i.e., the current pre-treatment pyridostigmine and huperzine, a proposed pre-treatment, are compared in primates. This is the first time primates are used to study the potential of pre-treatment with hyperzine. Indeed, previous studies with huperzine used nonprimate models which are not the most appropriate for pre-treatment in humans. Each medication is given via a subcutaneous mini-osmotic pump for 6 days at a delivery rate providing about 20% inhibition of red cell AChE activity. In this trial with only four primates, huperzine selectively inhibits red cell AChE activity whereas pyridostigmine also inhibits plasma butyrylcholinesterase (BuChE). This latter may act as endogenous scavenger of OP compounds helping to confer additional protection against OPs. During intoxication, the cumulative dose of soman needed to produce convulsions and epileptic activity is 1.55-fold higher in the animals pre-treated with huperzine compared to those pre-treated with pyridostigmine. Thus, replacing PYR by HUP for a subchronic pre-treatment of primates gives them better tolerance to the epileptic effects of soman.
