Sulfated cholecystokinin octapeptide in the rat: Pontomedullary distribution and modulation of the respiratory pattern

Résultat de recherche: Articleexamen par les pairs

8 Citations (Scopus)

Résumé

We performed anatomical and physiological studies to determine the site and actions of sulfated cholecystokinin octapeptide (CCK8-S) on breathing. Peptide locations were determined by combined immunodetection of CCK8-S- containing synaptic varicosities and retrograde labeling of medullary neurons projecting to the ventral respiratory group. Retrogradely labeled neurons and CCK8-S immunolabeled varicosities overlapped within the nuclei of the solitary tract, ventral respiratory group, and the Kolliker-Fuse nucleus. Additional CCK8-S immunoreactive terminals were located in the rostroventrolateral medullary reticular nucleus, lateral paragigantocellular reticular nucleus, and the caudal pontine reticular nucleus. The respiratory effects of CCK8-S, which binds to CCK(A) and CCK(B) receptors, were examined by intravenous injection in adult rats and by bath application in the in vitro neonatal rat brainstem - spinal cord preparation. CCK8-S produced an increase in the mean amplitude of diaphragmatic electromyogram (EMG) of 28 ± 35% (SD) and a decrease in mean respiratory interval of 13 ± 4% in vivo. In vitro, CCK8-S significantly increased inspiratory duration and decreased respiratory interval, primarily by shortening expiratory duration. CCK8- unsulfated, a specific agonist for CCK(B) receptors, did not produce these effects. CCK8-S effects in the in vitro preparation were partially blocked by the CCK receptor antagonist lorglumide (final bath concentration 600 nM). These results suggest that CCK8-S modulates the respiratory rhythm via CCK(A) receptors within one or more medullary or pontine respiratory groups in both neonatal and adult rats.

Langue d'origineEnglish
Pages (de-à)490-504
Nombre de pages15
JournalCanadian Journal of Physiology and Pharmacology
Volume77
Numéro de publication7
DOI
Statut de publicationPublished - 1999

ASJC Scopus Subject Areas

  • Physiology
  • Pharmacology
  • Physiology (medical)

PubMed: MeSH publication types

  • Journal Article
  • Research Support, Non-U.S. Gov't

Empreinte numérique

Plonger dans les sujets de recherche 'Sulfated cholecystokinin octapeptide in the rat: Pontomedullary distribution and modulation of the respiratory pattern'. Ensemble, ils forment une empreinte numérique unique.

Citer