ABSTRACT
It has been proposed that neurotrophin-3 acts in a manner that is opposed to nerve growth factor, especially in the modulation of heat hyperalgesia. Injury to the constriction of the infraorbital nerve (CION) is a well-established model of trigeminal neuropathic pain that leads to robust heat, cold, and mechanical hyperalgesia. Here, we assessed the effect of local neurotrophin-3 treatment on CION-induced hyperalgesia, and we examined some mechanisms related to the effect of neurotrophin-3. Neurotrophin-3 (1 µg/50 µl) injected into the upper lip of CION rats caused a significant and long-lasting reduction of CION-induced heat hyperalgesia, but failed to affect cold and mechanical hyperalgesia. Increased levels of neurotrophin-3 were detected in the injured nerve at the time point that represents the peak of heat hyperalgesia. The anti-hyperalgesic effect of neurotrophin-3 was markedly reduced in the presence of an antagonist of TrkA receptors (K-252a, 1 µg/50 µl). Moreover, association of lower doses of neurotrophin-3 with an antibody anti-nerve growth factor resulted in a synergistic anti-hyperalgesic effect in CION rats. Local injection of nerve growth factor (3 µg/50 µl) or the TRPV1 agonist capsaicin (1 µg/50 µl), but not neurotrophin-3 injection (1 µg/50 µl), resulted in long-lasting facial heat hyperalgesia, which was both significantly reduced by previous neurotrophin-3 local treatment. In conclusion, we suggest that neurotrophin-3 is a potent modulator of facial heat hyperalgesia, which may exert an inhibitory influence on the trkA pathway. Neurotrophin-3 treatment may represent a promising approach, especially in pain conditions associated with increased levels of nerve growth factor.
Subject(s)
Hyperalgesia/drug therapy , Nerve Growth Factor/metabolism , Neurotrophin 3/administration & dosage , Animals , Capsaicin/pharmacology , Facial Pain/drug therapy , Facial Pain/metabolism , Hot Temperature , Hyperalgesia/metabolism , Male , Rats , Rats, Wistar , Receptor, trkA/metabolism , Trigeminal Neuralgia/drug therapy , Trigeminal Neuralgia/metabolismABSTRACT
As modificações da medicina tornaram o conhecimento biomédico soberano, gerando a perda da relação médico-paciente, o que fomentou o movimento pela humanização. Na Universidade Federal do Paraná (UFPR), formou-se o projeto de extensão "ProCura - a arte da vida", a fim de implementar a humanização entre os alunos e em suas relações profissionais. Seus objetivos se baseiam nos pilares: relação estudante-paciente, relação estudante-estudante e formação teórico-reflexiva, e se subdividem nos grupos Cineclube, Clown e Contação de Histórias. De 2010 a 2012, 79 alunos participaram e atenderam 905 pacientes, 505 acompanhantes e 107 funcionários. Apesar de limitações de alcance no que concerne a atingir todos os alunos do Setor de Ciências da Saúde, o projeto pretende fomentar a discussão entre grupos e que seus ideais e atividades se espalhem e permeiem o meio acadêmico.
Changes in medicine have promoted biomedical knowledge to a position of sovereignty. Coupled with the decline of the physician-patient relationship, this has brought about the the humanization movement. At the Federal University of Paraná (UFPR), a community outreach project entitled "ProCura - the art of living" has been created to implement humanization among students and in their professional relationships. Its objectives are based on three pillars: student-patient relationship, student-student relationship and theoretical-reflexive training, subdivided into groups named Cineclube, Clown and Contação de Histórias. Between 2010 and 2012, 79 students participated in the project, attending to 905 to patients, 505 companions and 107 employees. Despite its limited scope as regards reaching all Department of Health Sciences students, the Project aims to promote discussion between groups and disseminate their ideals and activities throughout academic circles.
