Extracellular Ca2+ changes during transmitter application in the leech central nervous system
Research article published in Neuroscience letters (1996)
Abstract
Changes in extracellular Ca2+ concentration ([Ca2+]e) evoked by transmitters and transmitter agonists, respectively, and by elevation of bath K+ concentration were recorded in isolated segmental ganglia of the leech Hirudo medicinalis using Ca(2+)-selective microelectrodes. A 1-min bath application of kainate (10 microM), glutamate (1 mM), aspartate (1 mM), or carbachol (200 microM) decreased [Ca2+]e by up to 1 mM, whereas the inhibitory transmitters gamma-amino butyric acid (GABA, 100 microM) and serotonin (5-HT, 100 microM) did not change [Ca2+]e. The amplitude of the kainate-induced changes in [Ca2+]e increased with repetitive applications, and changes were blocked by 6-cyano-7-dinitroquinozaline-2,3-dione (CNQX). Elevation of bath K+ concentration from 4 to 40 mM led to a Ni(2+)-sensitive decrease in [Ca2+]e by 0.9 mM. Our results suggest that excitatory transmission in the leech central nervous system might be accompanied by substantial decreases in [Ca2+]e.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Resumen
Changes in extracellular Ca2+ concentration ([Ca2+]e) evoked by transmitters and transmitter agonists, respectively, and by elevation of bath K+ concentration were recorded in isolated segmental ganglia of the leech Hirudo medicinalis using Ca(2+)-selective microelectrodes.
Por qué esto importa para la hirudoterapia
Este estudio utilizó microelectrodos selectivos de Ca2+ para registrar cambios en la concentración extracelular de calcio en ganglios segmentarios aislados de Hirudo medicinalis durante la aplicación en baño de neurotransmisores y agonistas, hallando que los transmisores excitatorios (kainato, glutamato, aspartato, carbacol) disminuyeron el Ca2+ extracelular hasta 1 mM, mientras que los transmisores inhibitorios (GABA, serotonina) no lo hicieron. El trabajo contribuye a la comprensión neurofisiológica fundamental de la sanguijuela medicinal, la especie primaria empleada en hirudoterapia, iluminando los mecanismos básicos de señalización celular en este organismo. Sin embargo, se trata de un estudio in vitro de ganglios aislados que no investiga la terapia con sanguijuelas, el secretoma salival ni ninguna aplicación clínica; su relevancia para la hirudoterapia es indirecta, limitada a la neurobiología básica de la sanguijuela.
Citación
Extracellular Ca2+ changes during transmitter application in the leech central nervous system.
Lohr C, Rose C, Deitmer J · Neuroscience letters, 1996
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Añadido a la biblioteca ASH: March 18, 2026 · Última actualización del sitio: June 18, 2026