Further evidence that various 5-HT receptor subtypes modulate central respiratory activity: in vitro studies with SR 46349B.
The ability of SR 46349B [trans,4-([3Z)3-(2-dimethylaminoethyl)oxyimino- 3(2-flurophenyl)propen-1-yl]phenol hemifumarate], a 5-HT2 receptor antagonist, to block the changes in respiratory activity induced by serotonin was analysed by using brain stem-spinal cord preparations from newborn rats. The increases in respiratory frequency elicited by serotonin (and 5-HT1A receptor agonist) were not suppressed by SR 46349B. The tonic discharge of cervical motoneurons and the depression of inspiratory hypoglossal activity elicited by serotonin (and 5-HT2 receptor agonist) were reduced in a dose-dependent manner by SR 46349B. These results confirm that activation of 5-HT1A and 5-HT2 receptors influences respiratory frequency and motoneuronal output, respectively.
Biologie des Rythmes et du Développement, URA CNRS 1832, Faculté des Sciences et Techniques St Jérôme, Marseille, France.
R
R
Monteau
E
E
Di Pasquale
G
G
Hilaire
D000818:Animals; D001921:Brain / Q000502:physiology*; D005464:Fluorobenzenes / Q000494:pharmacology*; D010636:Phenols / Q000494:pharmacology*; D051381:Rats; D011985:Receptors, Serotonin / Q000502:physiology*; D012119:Respiration / Q000187:drug effects*; D012702:Serotonin Antagonists / Q000494:pharmacology*
D005464:Fluorobenzenes; D010636:Phenols; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; C076033:SR 46349B