Glial responses during evoked behaviors in the leech.
Glial cells can respond with membrane potential changes during electrically stimulated neuronal activity (Kuffler, Proc R Soc Lond B 168:1-21, 1967; Orkand, Oxford University Press, 1995). Their role in contributing to, or controlling, neural circuits underlying behaviors, however, is completely unknown. We have used semi-intact preparations of the leech Hirudo medicinalis, where behaviors can be elicited and monitored (Kristan et al., J Neurobiol 27:380-389, 1995), to record membrane responses of identified glial cells during whole-body shortening and during fictive swimming. Giant glial cells are located in the neuropil of segmental ganglia, where neuronal axons and dendrites establish numerous synaptic contacts (Coggeshall and Fawcett, J Neurophysiol 27:229-289, 1964). We report here that these glial cells hyperpolarize when the whole-body-shortening response is evoked but not during fictive swimming. To our knowledge, this is the first report that associates a specific behavior with glial cell responses.
Deitmer
J W
JW
Abteilung für Allgemeine Zoologie, Universität Kaiserslautern, Germany.
Kristan
W B
WB
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D004558:Electric Stimulation; D004594:Electrophysiology; D017952:Ganglia, Invertebrate / Q000166:cytology / Q000502:physiology; D007865:Leeches / Q000502:physiology*; D008564:Membrane Potentials / Q000502:physiology; D009457:Neuroglia / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D019581:Neuropil / Q000166:cytology / Q000502:physiology; D012018:Reflex / Q000502:physiology; D013550:Swimming / Q000502:physiology