Summary
High pressures of helium affect the physiology of the central nervous system in animals and humans. We examined these effects in rat hippocampal slices. The in vitro preparation displayed a reversible reduction in postsynaptic and antidromic field potentials of CA1 pyramidal cells, but no significant change in the amplitude of the afferent volley. Although the subliminal synaptic response of CA1 neurons was depressed, the ability of these cells to produce population spikes was enhanced. These changes resembled those previously found in vivo in the rat hippocampus. The present results support the hypothesis of a helium pressure-induced depolarization of hippocampal neurons. Other possible mechanisms are discussed.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Andersen P (1960) Interhippocampal impulses. II. Apical dendritic activation of CA1 neurons. Acta Physiol Scand 48: 178–208
Andersen P, Silfvenius H, Sundberg SH, Sveen O, Wigström H (1978) Functional characteristics of unmyelinated fibers in the hippocampal cortex. Brain Res 144: 11–18
Bennett PB (1975) The high pressure nervous syndrome: man. In: Bennett PB, Elliott DM (eds) The physiology and medecine of diving and compressed air work, London, pp 248–263
Brauer RW (1975) The high pressure nervous syndrome: animals. In: Bennett PB, Elliott DM (eds) The physiology and medecine of diving and compressed air work, London, pp 231–247
Brauer RW, Beaver RW, Lasher RD, Mc Call RD, Venters R (1979a) Comparative physiology of the high-pressure neurological syndrome — compression rate effects. J Appl Physiol Resp Environ Exercise Physiol 46: 128–135
Brauer RW, Mansfield WM, Beaver RW, Gillen HW (1979b) Stages in development of high pressure neurological syndrome in the mouse. J Appl Physiol Resp Environ Exercise Physiol 46: 756–765
Brauer RW, Hogan PM, Hugon M, Macdonald AG, Miller KW (1982) Patterns of interaction of effects of light metabolically inert gases with those of hydrostatic pressure as such a review. Undersea Biomed Res 9: 353–396
Campenot RB (1975) The effects of high hydrostatic pressure on transmission at the crustacean neuromuscular junction. Comp Biochem Physiol 52B: 133–140
Colton CA, Colton JS (1980) An electrophysiological analysis of oxygen and pressure on synaptic transmission. Brain Res 251: 221–227
Dudek FE, Andrew RD, MacVicar BA, Snow RV, Taylor CP (1963) Recent evidence for and possible significance of gap junctions and electrotonic synapses in the mammalian brain. In: Jasper HH, van Gelder NM (eds) Basic mechanisms of neuronal hyperexcitability. Liss, New York, pp 31–73
Dunwiddie TV, Lynch GS (1978) Long-term potentiation and depression of synaptic responses in the rat hippocampus: localization and frequency dependency. J Physiol (Lond) 276: 353–367
Fagni L, Weiss M, Pellet J, Hugon M (1982) The possible mechanisms of the high pressure-induced motor disturbances in the cat. Electroencephal Clin Neurophysiol 53: 590–601
Fagni L, Soumireu-Mourat B, Carlier E, Hugon M (1985) A study of spontaneous and evoked activity in the rat hippocampus under helium-oxygen high pressure. Electroenceph Clin Neurophysiol 60: 267–275
Grossman Y, Kendig JJ (1984) Pressure and temperature: time-dependent modulation of membrane properties in a bifurcating axon. J Neurophysiol 52: 692–708
Heinemann U, Lux HD, Gutnick MJ (1977) Extracellular free calcium and potassium during paroxysmal activity in the cerebral cortex of the cat. Exp Brain Res 27: 237–243
Hille B (1984) Ionic channels of excitable membranes. Sinauer Ass Inc, Sunderland Mass
Hugon M, Lemaire C (1975) Cycle d'excitabilité de la fibre motrice étudiée chez l'homme normal en hyperbarie à l'helium. Med Sub Hyp 11: 9–17
Kendig JJ, Trudell JR, Cohen EN (1975) Effects of pressure and anesthetics on conduction and synaptic transmission. J Pharmacol Exp Ther 195: 216–224
Kylstra JA, Nantz R, Crowe J, Wagner W, Saltzmann HA (1967) Hydraulic compression of mice to 166 atmospheres. Science 158: 793–794
Lømo T (1971) Patterns of activation in a monosynaptic cortical pathway: the peforant path input of the dentate area of the hippocampal formation. Exp Brain Res 12: 18–45
Lundgren CEG, Hornagen HC (1976) Hydrostatic pressure tolerance in liquid-breathing mice. In: Lambertsen CJ (ed) Underwater physiology, Vol V. Bethesda MD, pp 397–404
Racine R, Kairiiss E, Smith G (1981) Kindling: the evolution of the burst response versus enhancement. In: Wada JA (ed) Kindling 2. Raven Press, New York, pp 15–29
Rostain JC, Dumas JC, Gardette B, Imbert JP, Lemaire C (1984) Effects of addition of nitrogen during rapid compression of baboons. J Appl Physiol Respirat Exercise Physiol 57: 332–340
Rostain JC, Naquet R (1974) Le syndrome nerveux des hautes pressions: caractéristiques et évolution en fonction de divers modes de compression. Rev EEG Neurophysiol 4: 107–124
Sauter JFL, Braswell LM, Miller KW (1980) Action of anesthetics and high pressures on cholinergic membranes. Prog Anesthesiol 2: 199–207
Schwartzkroin PA (1980) Ionic and synaptic determinants of burst generation. In: Lockard JS, Ward AA (eds) Epilepsy: a window to brain mechanisms. Raven Press, New York, pp 83–95
Schwartzkroin PA, Prince DA (1978) Cellular and field potential properties of epileptogenic hippocampal slices. Brain Res 147: 117–130
Taylor CP, Dudek FE (1984) Excitation of hippocampal pyramidal cells by an electrical field effect. J Neurophysiol 52: 126–142
Taylor RF, Robertson RF (1980) Effects of normo- and hyperbaric pressure on an acetylcholine-binding proteoglycolipid from rat gastrocnemius tissue. J Neurochem 34: 1166–1174
Wann KT, Macdonald AG (1980) The effects of pressure on excitable cells. Comp Biochem Physiol 66A: 1–12
Wann KT, Macdonald AG, Harper AA, Ashford MLJ (1981) Transient versus steady-state effects of high hydrostatic pressure. In: Bachrach AJ, Matzen MM (eds) Underwater physiology,Vol VII. Undersea Med Soc, Bethesda, pp 621–627
Wong RKS, Traub RD (1983) Synchronized burst discharge in the disinhibited hippocampal slice. I. Initiation in the CA2-CA3 region. J Neurophysiol 49: 442–458
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Fagni, L., Zinebi, F. & Hugon, M. Evoked potential changes in rat hippocampal slices under helium pressure. Exp Brain Res 65, 513–519 (1987). https://doi.org/10.1007/BF00235974
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00235974