Membrane properties of microglial cells isolated from the leech central nervous system
| Autor: | R. R. Stewart |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
Serotonin
Time Factors Leech In Vitro Techniques Biology Ion Channels General Biochemistry Genetics and Molecular Biology Membrane Potentials Leeches Animals Nervous System Physiological Phenomena Channel blocker Patch clamp Evoked Potentials General Environmental Science Membrane potential General Immunology and Microbiology Cell Membrane General Medicine Ganglia Invertebrate Electrophysiology Membrane Biophysics Microglia General Agricultural and Biological Sciences Neuroscience Cation channel activity |
| Zdroj: | Proceedings of the Royal Society of London. Series B: Biological Sciences. 255:201-208 |
| ISSN: | 1471-2954 0962-8452 |
| Popis: | Membrane potentials and channel properties of microglial cells isolated from the leech central nervous system and maintained in culture on different substrates were investigated by using the patch-clamp technique. As expected, microglia on concanavalin A (con-A) were round and stationary, whereas those on extract of extracellular matrix (ECM) were spindle shaped and mobile. The mean membrane capacitance was 9 +/- 1 pF (s.e., n = 46), and the input resistance ranged from 0.135 G omega to 21 G omega with a mean of 4.2 +/- 1.6 G omega (n = 19). On-cell patches exhibited no single-channel activity. Voltage-dependent Na+, K+ and Ca2+ currents typical of neurons were absent. Currents evoked in response to voltage ramps from -100 mV to +100 mV or to steps of 4 s duration reversed in sign at or near 0 mV and exhibited single-channel activity of increasing amplitude for incrementally larger positive and negative voltage steps. No differences between the membrane properties of microglial cells on con-A and on ECM were evident. Currents were increased in fluid in which Na+ was substituted with K+, and were decreased when Na+ was substituted with N-methyl-D-glucamine. Varying external [Cl-] was without effect, as was addition to the fluid of 100 microM anthracene-9-carboxylate, a Cl- channel blocker. Together these characteristics indicated a cation channel. Bath application of 100 microM serotonin reversibly increased both inward and outward currents as well as single-channel activity. It is concluded that cultured microglial cells isolated from the adult leech have high membrane resistance and cation channel activity influenced by serotonin. |
| Databáze: | OpenAIRE |
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