The regulation of intracellular pH by identified glial cells and neurones in the central nervous system of the leech.
Research article published in The Journal of physiology (1987)
Abstract
1. Double-barrelled, neutral-carrier pH-sensitive micro-electrodes were used to measure the intracellular pH (pHi) and the pHi regulation of neuropile glial (n.g.) cells and of identified neurones of the leech Hirudo medicinalis. 2. The distribution of H+ in the n.g. cells and in the neurones was found not to be in electrical equilibrium. The mean pHi of the n.g. cells was 6.87 +/- 0.13 (mean +/- S.D. of mean here and for all following data n = 27) in HEPES-buffered leech saline (pHo = 7.4) and 7.18 +/- 0.19 (n = 13) in 2% CO2-11 mM-HCO3(-)-saline. The mean pHi was 7.28 +/- 0.1 (n = 20) in Retzius neurones and 7.32 +/- 0.15 (n = 12) in noxious neurones in HEPES-buffered leech saline, and 7.20 +/- 0.15 (n = 10) and 7.27 +/- 0.16 (n = 6) in 2% CO2-11 mM-HCO3(-)-buffered saline in these two types of neurones, respectively. 3. The cytoplasmic buffering power, as calculated by the change in pHi following the change from 2% CO2-11 mM-HCO3- to 5% CO2-22 mM-HCO3- in the leech saline, was 20-30 mM/pH unit in the n.g. cells and between 12 and 33 mM/pH unit in the neurones. 4. The recovery of pHi in n.g. cells from an experimentally induced acidification (addition and removal of 20 mM-NH4Cl) was dependent on the presence of external Na+. Independent of the buffer system used, pHi recovery was inhibited when external Na+ was exchanged by N-methyl-D-glucamine. Amiloride (2-3 mM) reduced the rate of pHi recovery by about 50% in these n.g. cells. 5. In CO2-HCO3(-)-free saline, or in the presence of the anion exchange blocker 4-acetamido-4'-isothiocyanostilbene-2, 2'-disulphonic acid (SITS, 0.5 mM), pHi recovery from an acid load was often slowed by up to 50% in n.g. cells. This suggests that there is a significant contribution of a HCO3(-)-dependent membrane transport to pHi regulation in n.g. cells. 6. When a HEPES-buffered saline was exchanged by a 2% CO2-11 mM-HCO3(-)-buffered saline, the pHi of n.g. cells increased by 0.31 pH units. This alkaline shift was reversible upon removal of the CO2-HCO3- and was absent in the Na+-free saline. It was not inhibited by 1 mM-furosemide or by 0.5 mM-SITS.(ABSTRACT TRUNCATED AT 400 WORDS)
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Resumen
1. Double-barrelled, neutral-carrier pH-sensitive micro-electrodes were used to measure the intracellular pH (pHi) and the pHi regulation of neuropile glial (n.g.) cells and of identified neurones of the leech Hirudo medicinalis.
Por qué esto importa para la hirudoterapia
Este estudio examinó la regulación del pH intracelular en células gliales y neuronas identificadas dentro del sistema nervioso central de la sanguijuela medicinal, Hirudo medicinalis. Al caracterizar la neurofisiología fundamental y los mecanismos homeostáticos de la sanguijuela, el estudio aporta conocimientos biológicos básicos sobre el propio organismo utilizado en la hirudoterapia clínica. Sin embargo, su relevancia para la American Society of Hirudotherapy es estrictamente fundacional, ya que no investiga el secretoma de la sanguijuela, aplicaciones terapéuticas ni ningún resultado clínico relacionado con la terapia con sanguijuelas. El alcance se limita a la fisiología celular in vitro.
Citación
The regulation of intracellular pH by identified glial cells and neurones in the central nervous system of the leech.
Deitmer et al. · The Journal of physiology, 1987
Contexto clínico relacionado
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Añadido a la biblioteca ASH: May 28, 2026 · Última actualización del sitio: 18 de junio de 2026