title: A study of spontaneous and evoked activity in the rat hippocampus under helium-oxygen high pressure.
abstract: High pressures affect the physiology of the central nervous system. For a better understanding of this effect, we examined the hippocampal activity in the rat under high pressures (91 bars) of helium-oxygen. Effects of high pressure on hippocampal physiology are: an abnormally sustained 5-8 Hz pattern of spontaneous activity, followed, in some cases, by seizures; a marked decrease in the responses of CA1 pyramidal cells to stimulation of their commissural afferents; and a 50% decrease in the afterdischarge threshold. On the basis of the relatively well understood hippocampal physiology in normobaric conditions, our observations suggest that high pressures induce hypoexcitability of afferents and/or target cells.
authors.forename: L
authors.initials: L
authors.lastname: Fagni
authors.forename: B
authors.initials: B
authors.lastname: Soumireu-Mourat
authors.forename: E
authors.initials: E
authors.lastname: Carlier
authors.forename: M
authors.initials: M
authors.lastname: Hugon
mesh_terms: D000818:Animals; D004056:Differential Threshold; D004566:Electrodes; D004569:Electroencephalography; D004827:Epilepsy / Q000209:etiology; D005071:Evoked Potentials; D006371:Helium / Q000494:pharmacology*; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D009043:Motor Activity; D010100:Oxygen / Q000494:pharmacology*; D011312:Pressure; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D006371:Helium; D010100:Oxygen