Hydrogen sulfide inhibits giant depolarizing potentials and abolishes epileptiform activity of neonatal rat hippocampal slices. (6th January 2017)

• Record Type: Journal Article
• Authors: Yakovlev, Aleksey V.; Kurmasheva, Evgeniya D.; Giniatullin, Rashid; Khalilov, Ilgam; Sitdikova, Guzel F.
• Is Part Of: Neuroscience. Volume 340(2017)
• Page Start: 153
• Page End: 165
• Publication Date: 2017-01-06
• Subjects: 3-MST 3-mercaptopyruvate sulfurtransferase -- ACSF artificial cerebrospinal fluid -- AMPA α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid -- CAT cysteine aminotransferase -- CBS cystathionine beta-synthase -- CNQX 6-cyano-7-nitroquinoxaline-2, 3dione -- CSE cystathionine gamma-lyase -- DAO d-amino acid oxidase -- d-APV d-2-amino-5-phosphopentanoate -- EGTA ethylene glycol-bis(2-aminoethylether)-N, N, N′, N′-tetraacetic acid -- GABA γ-aminobutyric acid -- GDPs giant depolarizing potentials -- H2S hydrogen sulfide -- HEPES 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid -- MUA multi-unit activity -- NaHS sodium hydrosulfide -- NMDA N-methyl-d-aspartate -- TEA tetraethylammonium -- TTX tetrodotoxin; hydrogen sulfide -- neonatal hippocampus -- giant depolarizing potentials -- membrane potential -- interictal-like events -- NMDA-mediated currents; Neurochemistry -- Periodicals; Neurophysiology -- Periodicals; Neurology -- Periodicals; Neurochimie -- Périodiques; Neurophysiologie -- Périodiques; Neurochemistry; Neurophysiology; Electronic journals; Periodicals; Electronic journals; 612.8
• DOI: 10.1016/j.neuroscience.2016.10.051
• Languages: English
• ISSNs: 0306-4522

Abstract

Highlights: Exogenous and endogenous H2 S decreases network activity in the immature rat hippocampus. H2 S evokes TTX-resistant depolarizations of neurons and reduces outward K + currents. H2 S decreases NMDA-mediated currents without effects on GABAA and AMPA/kainate responses. H2 S completely abolishes bicuculline-evoked epileptiform activity in the hippocampus of neonatal rats. Abstract: Hydrogen sulfide (H2 S) is an endogenous gasotransmitter with neuroprotective properties that participates in the regulation of transmitter release and neuronal excitability in various brain structures. The role of H2 S in the growth and maturation of neural networks however remains unclear. The aim of the present study is to reveal the effects of H2 S on neuronal spontaneous activity relevant to neuronal maturation in hippocampal slices of neonatal rats. Sodium hydrosulfide (NaHS) (100 μM), a classical donor of H2 S produced a biphasic effect with initial activation and subsequent concentration-dependent suppression of network-driven giant depolarizing potentials (GDPs) and neuronal spiking activity. Likewise, the substrate of H2 S synthesisl -cysteine (1 mM) induced an initial increase followed by an inhibition of GDPs and spiking activity. Our experiments indicate that the increase in initial discharge activity by NaHS is evoked by neuronal depolarization which is partially mediated by a reduction of outward K + currents. The subsequent decrease in the neuronal activity by H2 S appears to be due to the rightward shift of activation and inactivation of voltage-gated Na + currents, thus preventing network activity. NaHS also reduced N-methyl-d -aspartate (NMDA)-mediated currents, without essential effect on AMPA/kainate or GABAA -mediated currents. Finally, H2 S abolished the interictal-like events induced by bicuculline. In summary, our results suggest that through the inhibitory action on voltage-gated Na + channels and NMDA receptors, H2 S prevents the enhanced neuronal excitability typical to early hippocampal networks.