Mediation of serotonin-induced hyperventilation via 5-HT3-receptor in European eel Anguilla anguilla.
The effects of serotonin (5-hydroxytryptamine) on ventilation were investigated by continuous measurements of intrabuccal pressure in unrestrained eel. Intravenous administration of 5-hydroxytryptamine (30 micrograms.kg-1) caused a large increase in ventilatory frequency (+ 100%) and amplitude (+ 140%). The 5-hydroxytryptamine-induced hyperventilation was blocked by the 5-HT3-receptor antagonists metoclopramide (1.0 mg.kg-1) or MDL72222 (1.0 mg.kg-1), and was insensitive to the 5-HT1/2-receptor antagonist methysergide (3.0 mg.kg-1) and to the 5-HT4-receptor antagonist DAU 6285 CL (3.0 mg.kg-1). The hyperventilatory response to 5-hydroxytryptamine could be mimicked by the 5-HT3 receptor agonist 1-phenylbiguanide (300 micrograms.kg-1). These results strongly implicate the 5-HT3-receptor as the mediator of the 5-hydroxytryptamine-induced hyperventilation in eel.
Janvier
J J
JJ
Faculté des Sciences et Techniques, Laboratoire de Physiologie Animale, Brest, France.
Peyraud-Waïtzenegger
M
M
Soulier
P
P
D000811:Anguilla / Q000502:physiology*; D000818:Animals; D001562:Benzimidazoles / Q000494:pharmacology; D001645:Biguanides / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D006985:Hyperventilation / Q000139:chemically induced* / Q000503:physiopathology / Q000517:prevention & control; D007275:Injections, Intravenous; D008784:Methysergide / Q000494:pharmacology; D008787:Metoclopramide / Q000494:pharmacology; D011985:Receptors, Serotonin / Q000187:drug effects* / Q000502:physiology; D044406:Receptors, Serotonin, 5-HT3; D012119:Respiration / Q000187:drug effects / Q000502:physiology; D012701:Serotonin / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D012702:Serotonin Antagonists / Q000494:pharmacology; D014326:Tropanes / Q000494:pharmacology
D001562:Benzimidazoles; D001645:Biguanides; D019086:Bridged Bicyclo Compounds, Heterocyclic; D011985:Receptors, Serotonin; D044406:Receptors, Serotonin, 5-HT3; D012702:Serotonin Antagonists; D014326:Tropanes; C074390:DAU 6285; D012701:Serotonin; D008787:Metoclopramide; C042253:bemesetron; C008846:phenyl biguanide; D008784:Methysergide