M4-muscarinic acetylcholine receptor into the pedunculopontine tegmental nucleus mediates respiratory modulation of conscious rats

Autor(es)

Lima, Janayna D. ^[1] ; Sobrinho, Cleyton R. ^[1] ; Santos, Leonardo K. ^[1] ; Takakura, Ana C. ^[2] ; Moreira, Thiago S. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Physiol & Biophys, BR-05508 Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Dept Pharmacol, BR-05508 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Respiratory Physiology & Neurobiology; v. 269, NOV 2019.
• Citações Web of Science: 0

Resumo

The pedunculopontine tegmental nucleus (PPTg) has been shown to have important functions relevant to the regulation of behavioral states and various motor control systems, including breathing control. The PPTg is considered an important nucleus in the mesopontine region with considerably cholinergic input to the ventral respiratory column. In addition, recent studies indicate that cholinergic innervation of the ventral respiratory column may play an important role in modulation of breathing. Here, we investigated the cholinergic stimulation of the PPTg and the changes in breathing output in conscious rats. Male Wistar rats (280-350 g, N = 5-12/group) with unilateral stainless steel cannula implanted into the PPTg were used. Respiratory parameters (tidal volume (V-T), respiratory frequency (f(R)) and ventilation (V-E)) were analyzed by whole body plethysmography. In unrestrained awake rats, unilateral injection of the cholinergic muscarinic agonist carbachol (10 mM-100 nL) in the PPTg decreased f(R), and increase V-T, without changing V-E. The changes in f(R) and V-T elicited by carbachol into the PPTg are abolished by previous blockade of the M4 muscarinic cholinergic receptors tropicamide into the PPTg. No significant changes in f(R) and V-T elicited by carbachol were observed after blockade of the M1 and/or M3 muscarinic cholinergic receptors pirenzepine or 4-DAMP into the PPTg. Our data suggest that the changes in f(R) and V-T produced by muscarinic cholinergic stimulation of PPTg is presumably mediated through a Gi-coupled M4 muscarinic receptors. (AU)

• 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: 15/23376-1 - Núcleo retrotrapezóide, quimiossensibilidade central e automaticidade respiratória
• Beneficiário: Thiago dos Santos Moreira
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 15/12827-2 - Sinalização colinérgica e ventilação: ação modulatória do núcleo tegmental peduncúlo-pontino sobre o núcleo retrotrapezóide
• Beneficiário: Cleyton Roberto Sobrinho
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 17/01380-2 - Interação entre o núcleo tegmental pedúnculo pontino e centros respiratórios bulbares na modulação do padrão respiratório
• Beneficiário: Janayna Dias Lima
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto