| Texto completo | |
| Autor(es): |
Silva, Josiane do N.
[1]
;
Oliveira, Luiz M.
[1]
;
Souza, Felipe C.
[1]
;
Moreira, Thiago S.
[2]
;
Takakura, Ana C.
[1]
Número total de Autores: 5
|
| Afiliação do(s) autor(es): | [1] Univ Sao Paulo, Inst Ciencias Biomed, Dept Farmacol, Sao Paulo - Brazil
[2] Univ Sao Paulo, Inst Ciencias Biomed, Dept Fisiol & Biofis, Sao Paulo - Brazil
Número total de Afiliações: 2
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Journal of Neurophysiology; v. 123, n. 5, p. 1933-1943, MAY 2020. |
| Citações Web of Science: | 0 |
| Resumo | |
The parafacial respiratory group (pFRG), located in the lateral aspect of the rostroventral lateral medulla, has been described as a conditional expiratory oscillator that emerges mainly in conditions of high metabolic challenges to increase breathing. The convergence of inhibitory and excitatory inputs to pFRG and the generation of active expiration may be more complex than previously thought. We hypothesized that the medullary raphe, a region that has long been described to be involved in breathing activity, is also responsible for the expiratory activity under hypercapnic condition. To test this hypothesis. we performed anatomical and physiological experiments in urethane-anesthetized adult male Wistar rats. Our data showed anatomical projections from serotonergic (5-HT-ergic) and GABAergic neurons of raphe magnus (RMg) and obscurus (ROb) to the pFRG region. Pharmacological inhibition of RMg or ROb with muscimol (60 pmo1/30 nL) did not change the frequency or amplitude of diaphragm activity and did not generate active expiration. However, under hypercapnia (9-10% CO2), the inhibition of RMg or ROb increased the amplitude of abdominal activity, without changing the increased amplitude of diaphragm activity. Depletion of serotonergic neurons with saporin anti-SERT injections into ROb and RMg did not increase the amplitude of abdominal activity during hypercapnia. These results show that the presumably GABAergic neurons within the RMg and ROb may be the inhibitory source to modulate the activity of pFRG during hypercapnia condition. NEW \& NOTEWORTHY Medullary raphe has been involved in the inspiratory response to central chemoreflex; however, these reports have never addressed the role of raphe neurons on active expiration induced by hypercapnia. Here, we showed that a subset of GABA cells within the medullary raphe directly project to the parafacial respiratory region, modulating active expiration under high levels of CO2. (AU) | |
| Processo FAPESP: | 15/23376-1 - Núcleo retrotrapezóide, quimiossensibilidade central e automaticidade respiratória |
| Beneficiário: | Thiago dos Santos Moreira |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 16/23281-3 - Regiões encefálicas responsáveis pela neuroplasticidade observada na resposta respiratória induzida por hipercapnia em modelo animal de Doença de Parkinson |
| Beneficiário: | Ana Carolina Takakura Moreira |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 14/23418-3 - Caracterização anatomofuncional da fonte de inibição dos neurônios do núcleo retrotrapezóide envolvidos no controle da expiração ativa |
| Beneficiário: | Josiane do Nascimento Silva |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |