RESUMO
PURPOSE: To evaluate the effects of Dexmedetomidine (Dex) on spinal pathology and inflammatory factor in a rat model of Diabetic neuropathic pain (DNP). METHODS: The rats were divided into 3 groups (eight in each group): normal group (N group), diabetic neuropathic pain model group (DNP group), and DNP model with dexmedetomidine (Dex group). The rat model of diabetes was established with intraperitoneal streptozotocin (STZ) injections. Nerve cell ultrastructure was evaluated with transmission electron microscopy (TEM). The mechanical withdrawal threshold (MWT) and motor nerve conduction velocity (MNCV) tests documented that DNP rat model was characterized by a decreased pain threshold and nerve conduction velocity. RESULTS: Dex restored the phenotype of neurocytes, reduced the extent of demyelination and improved MWT and MNCV of DNP-treated rats (P=0.01, P=0.038, respectively). The expression of three pain-and inflammation-associated factors (P2X4, NLRP3, and IL-IP) was significantly upregulated at the protein level in DNP rats, and this change was reversed by Dex administration (P=0.0022, P=0.0092, P=0.0028, respectively). CONCLUSION: The P2X4/NLRP3 signaling pathway is implicated in the development and presence of DNP in vivo, and Dex protects from this disorder.
Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Dexmedetomidina/farmacologia , Neuropatias Diabéticas/tratamento farmacológico , Proteína 3 que Contém Domínio de Pirina da Família NLR/análise , Receptores Purinérgicos P2X4/análise , Coluna Vertebral/efeitos dos fármacos , Animais , Western Blotting , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Neuropatias Diabéticas/patologia , Modelos Animais de Doenças , Interleucina-1beta/análise , Interleucina-1beta/efeitos dos fármacos , Masculino , Microscopia Eletrônica de Transmissão , Proteína 3 que Contém Domínio de Pirina da Família NLR/efeitos dos fármacos , Condução Nervosa/efeitos dos fármacos , Limiar da Dor , Distribuição Aleatória , Ratos Sprague-Dawley , Receptores Purinérgicos P2X4/efeitos dos fármacos , Reprodutibilidade dos Testes , Transdução de Sinais/efeitos dos fármacos , Coluna Vertebral/patologia , Estreptozocina , Nervo Sural/efeitos dos fármacos , Nervo Sural/patologia , Fatores de TempoRESUMO
Abstract Purpose: To evaluate the effects of Dexmedetomidine (Dex) on spinal pathology and inflammatory factor in a rat model of Diabetic neuropathic pain (DNP). Methods: The rats were divided into 3 groups (eight in each group): normal group (N group), diabetic neuropathic pain model group (DNP group), and DNP model with dexmedetomidine (Dex group). The rat model of diabetes was established with intraperitoneal streptozotocin (STZ) injections. Nerve cell ultrastructure was evaluated with transmission electron microscopy (TEM). The mechanical withdrawal threshold (MWT) and motor nerve conduction velocity (MNCV) tests documented that DNP rat model was characterized by a decreased pain threshold and nerve conduction velocity. Results: Dex restored the phenotype of neurocytes, reduced the extent of demyelination and improved MWT and MNCV of DNP-treated rats (P=0.01, P=0.038, respectively). The expression of three pain-and inflammation-associated factors (P2X4, NLRP3, and IL-IP) was significantly upregulated at the protein level in DNP rats, and this change was reversed by Dex administration (P=0.0022, P=0.0092, P=0.0028, respectively). Conclusion: The P2X4/NLRP3 signaling pathway is implicated in the development and presence of DNP in vivo, and Dex protects from this disorder.