Abstract
The effect of changing extracellular pH (pH e ) on the membrane potential of silent cells in brain slices taken from the ventral surface layer of the rat medulla oblongata was compared to the response of silent cells in dorsal slices. In both slices, about 50% of cells showed no significant alteration in their membrane potential when they were exposed to acid solution. However, in the ventral slice, 44% of cells were slowly depolarized by H+ without accompanying significant changes in membrane resistance. In the dorsal medulla, acid solution caused a slight and slow hyperpolarization of 34% of the cells, although a few were slightly depolarized. These silent cells were incapable of initiating action potentials and were assumed to be glial cells. After depression of the release of neurotransmitter(s) in the slice by reducing the [Ca2+] e and increasing the [Mg2+] e , silent cells were not depolarized by H+. A putative transmitter acetylcholine depolarized non-specifically the silent cell membrane.
It was concluded that the slow depolarization of the silent cell by H+ could not be considered to be the H+-receptor potential and seemed to be dependent upon intact synaptic connections in the slice. Possible mechanisms of silent cell depolarization in the ventral medulla are discussed considering the corresponding neuronal excitation by H+ in the central chemosensitive structures.
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Akaike, N., Noma, A., Sato, M.: Frog taste cell response to chemical stimuli. Proc. Jap. Acad.49, 464–469 (1973)
Brightman, M. W., Albers, R. W.: Species differences in the distribution of extraneuronal cholinesterase within the vertebrate central nervous system. J. Neurochem.4, 244–250 (1959)
Carpenter, D. O., Hubbard, J. H., Humphrey, D. R., Thompson, H. K., Marshall, W. H.: Carbon dioxide effects on nerve cell function. In: Carbon dioxide and metabolic regulations (G. Nahas and K. E. Schaefer, eds.), pp. 49–62. New York: Springer 1974
Cohen, J. A., Osterbaan, R. A.: The interaction of acetylcholinesterase with substrate. In: Handbuch der Experimentellen Pharmakologie XV. Cholinesterase and Anticholinesterase Agents (Chapter 7, The active site of acetylcholinesterase and related esterases and its reactivity towards substrates and inhibitors) (G. B. Koelle, ed.), pp. 300–316. Berlin-Göttingen-Heidelberg: Springer 1963
Cragg, P., Patterson, L., Purves, M. J.: The pH of brain extracellular fluid in the cat. J. Physiol. (Lond.)272, 137–166 (1977)
Fukuda, Y., Honda, Y.: pH-sensitive cells at ventro-lateral surface of the rat medulla oblongata. Nature New Biol.256, 317–318 (1975)
Fukuda, Y., Honda, Y.: pH sensitivity of cells located at the ventrolateral surface of the cat medulla oblongata in vitro. Pflügers Arch.364, 243–247 (1976)
Fukuda, Y., Loeschcke, H. H.: Effect of H+ on spontaneous neuronal activity in the surface layer of the rat medulla oblongata in vitro. Pflügers Arch.371, 125–134 (1977)
Grossman, R. G., Hampton, T.: Depolarization of cortical glial cells during electrocortical activity. Brain Res.11, 316–324 (1968)
Hori, T., Roth, G. L., Yamamoto, Y. S.: Respiratory sensitivity of rat brain-stem surface to chemical stimuli. J. Appl. Physiol.28, 721–724 (1970)
Hubbard, J. I., Jones, S. F., Landau, E. M.: On the mechanism by which calcium and magnesium affect the spontaneous release of transmitter from mammalian motor nerve terminals. J. Physiol. (Lond.)194, 355–380 (1968)
Karahashi, Y., Goldring, S.: Intracellular potentials from ‘Idle’ cells in cerebral cortex of cat. Electroenceph. Clin. Neurophysiol.20, 600–607 (1966)
Kelly, J. P., Van Essen, D. C.: Cell structure and function in the visual cortex of the cat. J. Physiol. (Lond.)238, 515–547 (1974)
Kolle, G. B.: The histochemical identification of acetylcholinesterase in cholinergic, adrenergic and sensory neurons. J. Pharmacol. Exp. Ther.114, 167–184 (1955)
Krnjević, K., Schwartz, S.: Some properties of unresponsible cells in the cerebral cortex. Exp. Brain Res.3, 306–319 (1967)
Krnjevié, K.: Chemical nature of synaptic transmission in vertebrates. Physiol. Rev.54, 418–540 (1974)
Kuffler, S. W., Nicholls, J. G.: The physiology of neuroglial cells. Ergeb. Physiol.57, 1–90 (1966)
Kuffler, S. W., Nicholls, J. G.: From neuron to brain: A cellular approach to the function of the nervous system, pp. 255–288. Sunderland, Massachusets: Sinauer Associates, INC. Publishers 1976
Leusen, I.: Chemosensitivity of the respiratory center. Influence of CO2 in the cerebral ventricles on respiration. Am. J. Physiol.176, 39–44 (1954)
Leusen, I.: Chemosensitivity of the respiratory center. Influence of changes in the H+ and total buffer concentrations in the cerebral ventricles on respiration. Am. J. Physiol.176, 45–51 (1954)
Loescheke, H. H., Koepchen, H. P., Gertz, K. H.: Über den Einfluß von Wasserstoffionenkonzentration und CO2-Druck im Liquor cerebrospinalis auf die Atmung. Pflügers Arch. Ges. Physiol.266, 569–585 (1958)
Loeschcke, H. H., de Lattre, J., Schläfke, M. E., Trouth, C. O.: Effects on respiration and circulation of electrically stimulating the ventral surface of the medulla oblongata. Respir. Physiol.10, 184–197 (1970)
Loeschcke, H. H.: Central nervous chemoreceptors. In: Respiration physiology (J. G. Widdicombe, ed.), MTP International Review of Science, Physiology Series Vol. 2, pp. 167–196. London: Butterworths 1974
Mitchell, R. A., Loeschcke, H. H., Massion, W. H., Severinghaus, J. W.: Respiratory response mediated through superficial chemosensitive areas on the medulla. J. Appl. Physiol.18, 523–533 (1963)
Ozeki, M.: Conductance change associated with receptor potentials of gustatory cells in rat. J. Gen. Physiol.58, 688–699 (1971)
Pokorski, M.: Neurophysiological studies on central chemosensor in medullary ventrolateral areas. Am. J. Physiol.230, 1288–1295 (1976)
Ransom, B. R., Goldring, S.: Ionic determinants of membrane potential of cells presumed to be glia in cerebral cortex of cat. J. Neurophysiol.36, 855–868 (1973)
Ransom, B. R., Goldring, S.: Slow depolarization in cells presumed to be glia in cerebral cortex of cat. J. Neurophysiol.36, 869–878 (1973)
Richards, C. D., Sercombe, R.: Calcium, magnesium and the electrical activity of guinea-pig olfactory cortex in vitro. J. Physiol. (Lond.)211, 571–584 (1970)
Schläfke, M. E., Loeschcke, H. H.: Lokalisation eines an der Regulation von Atmung und Kreislauf beteiligten Gebietes an den ventralen Oberflächen der Medulla oblongata durch Kälteblockade. Pflügers Arch. Ges. Physiol.297, 201–220 (1967)
Schläfke, M. E., Pokorski, M., See, W. R., Prill, P. K., Loeschcke, H. H.: Chemosensitive neurons on the ventral medullary surface. Bull. Physiopath. Resp.11, 277–284 (1975)
Somjen, G. G.: Evoked sustained focal potentials and membrane potential of neurons and of unresponsive cells of the spinal cord. J. Neurophysiol.33, 562–582 (1970)
Somjen, G. G.: Electrophysiology of neuroglia. Ann. Rev. Physiol.37, 163–190 (1975)
Takahashi, K.: Slow and fast groups of pyramidal tract cells and their respective membrane properties. J. Neurophysiol.28, 908–924 (1965)
Werblin, F. S., Dowling, J. E.: Organization of the retina of the mudpuppy,Necturus Maculosus: II. Intracellular recording. J. Neurophysiol.32, 339–355 (1969)
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Fukuda, Y., Honda, Y., Schläfke, M.E. et al. Effect of H+ on the membrane potential of silent cells in the ventral and dorsal surface layers of the rat medulla in vitro. Pflugers Arch. 376, 229–235 (1978). https://doi.org/10.1007/BF00584955
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DOI: https://doi.org/10.1007/BF00584955