title: Effects of oxytocin on GABA signalling in the foetal brain during delivery.
abstract: Oxytocin (OXT) exerts multiple effects in the adult central nervous system. However, little is known about the effects of OXT on foetal neurons during delivery, at the time when a surge of OXT occurs. In a recent study, the effects of OXT on gamma-aminobutyric acid (GABA) signalling have been reported in foetal and newborn rats. In the immature rat hippocampal and neocortical neurons at birth, endogenous OXT induced a switch in the action of GABA from excitatory to inhibitory. This excitatory-to-inhibitory switch was caused by a switch in the polarity of the GABAergic responses from depolarizing to hyperpolarizing, reflecting a decrease in the intracellular chloride concentration. The effects of OXT were mimicked and occluded by bumetanide, a selective blocker of the chloride co-transporter NKCC1, suggesting that the effects of OXT involve inhibition of NKCC1. Neuronal death caused by anoxic-aglycaemic episodes was substantially delayed in the foetal hippocampus by endogenous OXT. These findings suggest that OXT plays important role in the preparation of the foetal brain to delivery.
authors.affiliation: INMED-INSERM U29, Université de la Méditerranée, Marseille, France.
authors.forename: Rustem
authors.initials: R
authors.lastname: Khazipov
authors.forename: Roman
authors.initials: R
authors.lastname: Tyzio
authors.forename: Yehezkel
authors.initials: Y
authors.lastname: Ben-Ari
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001921:Brain / Q000196:embryology*; D036861:Delivery, Obstetric; D005260:Female; D005333:Fetus / Q000502:physiology; D006801:Humans; D007743:Labor, Obstetric / Q000502:physiology; D007774:Lactation / Q000502:physiology; D009457:Neuroglia / Q000502:physiology; D009474:Neurons / Q000502:physiology; D010121:Oxytocin / Q000494:pharmacology*; D011247:Pregnancy; D028021:Sodium-Potassium-Chloride Symporters / Q000502:physiology; D064506:Solute Carrier Family 12, Member 2; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
chemical_list: C578877:SLC12A2 protein, human; C578879:Slc12a2 protein, rat; D028021:Sodium-Potassium-Chloride Symporters; D064506:Solute Carrier Family 12, Member 2; D010121:Oxytocin; D005680:gamma-Aminobutyric Acid