[Local GABA-ergic modulation of serotonergic neuron activity in the nucleus raphe magnus].
In voltage-clamp experimental on slices of the rat brainstem the effects of 5-HT and GABA on serotonergic neurons of nucleus raphe magnus were investigated. Local applications of 5-HT induced an increase in IPCSs frequency and amplitude in 45% of serotonergic cells. The effect suppressed by the blocker of fast sodium channels tetradotoxin. Antagonist of GABA receptor gabazine blocked IPSCs in neurons both sensitive and non-sensitive to 5-HT action. Applications of GABA induced a membrane current (I(GABA)), which was completely blocked by gabazine. The data suggest self-control of the activity of serotonergic neurons in nucleus raphe magnus by negative feedback loop via local GABAergic interneurons.
A N
AN
Iniushkin
N A
NA
Merkulova
A O
AO
Orlova
E M
EM
Iniushkina
D000818:Animals; D025461:Feedback, Physiological; D058787:GABA-A Receptor Antagonists; D066298:In Vitro Techniques; D015640:Ion Channel Gating; D008297:Male; D008564:Membrane Potentials; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D011724:Pyridazines / Q000494:pharmacology; D011903:Raphe Nuclei / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000494:pharmacology / Q000502:physiology*; D015222:Sodium Channels / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology / Q000502:physiology*
D058787:GABA-A Receptor Antagonists; D011724:Pyridazines; D015222:Sodium Channels; D012701:Serotonin; D013779:Tetrodotoxin; D005680:gamma-Aminobutyric Acid; C049853:gabazine