Inhibitory Effect of Endomorphin-2 Binding to the µ-Opioid Receptor in the Rat Pre-Bötzinger Complex on the Breathing Activity.
Mol Neurobiol
; 54(1): 461-469, 2017 01.
Article
en En
| MEDLINE
| ID: mdl-26742523
ABSTRACT
Opiates are commonly used analgesics that often cause clinical respiratory depression. However, their underlying mechanisms remain unclear. Endomorphin-2 (EM2) is a novel, endogenous tetrapeptide opioid with very high affinity and selectivity for the µ-opioid receptor (MOR). The pre-Bötzinger complex (pre-BötC) is considered the center of respiratory rhythm generation, and the synaptic connections in this region are essential for respiratory rhythm. The present study identified EM2-like immunoreactive (LI) axonal terminals in the pre-BötC of adult rats. Some EM2-LI axonal terminals made principally symmetric synapses with neurokinin 1 receptor (NK1R)-LI or MOR-LI neuronal dendritic processes in the pre-BötC. Unilateral microinjection of EM2 into the pre-BötC decreased breathing frequency and amplitude. A prior microinjection of the selective MOR antagonist ß-funaltrexamine (ß-FNA) into the pre-BötC prevented the effects of EM2. The present results suggest that EM2-LI axonal terminals modulate NK1R-expressing neurons in the pre-BötC and that EM2 plays a role in respiratory depression through MORs in the pre-BötC.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Oligopéptidos
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Tronco Encefálico
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Mecánica Respiratoria
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Receptores Opioides mu
Límite:
Animals
Idioma:
En
Revista:
Mol Neurobiol
Asunto de la revista:
BIOLOGIA MOLECULAR
/
NEUROLOGIA
Año:
2017
Tipo del documento:
Article