Some observations made by intracellular recordings in a primary astrocyte culture and a glioblastoma '138 MG'.
Intracellular recordings were performed in a primary astrocyte culture from rat brain and in a human glioblastoma cell line, 138 MG. The technique proved insufficient to verify the heterogeneous composition of the primary astrocyte culture, since this study shows most cells present in the culture to have similar resting membrane potential, membrane impedance, membrane potential/impedance relationship and K+-sensitivity. With the exception of macrophages, identified by their response to externally applied yeast particles, the results do not allow the identification of different cells that are known to be present. The membrane potential of the primary astrocyte was -68 +/- 14 mV, and the membrane potential of the 138 MG cells -37 +/- 15 mV. The membrane potential of cells in the primary culture have a K+-sensitivity resembling that of astrocytes in situ, whereas the K+-sensitivity of 138 MG more resemble that of a dedifferentiated cell. A reduction of 0.95 mm Ca2+ to o mM depolarizes the astrocyte with 9.6 mV and hyperpolarizes the glioma cell 2.6 mV.
D000818:Animals; D001253:Astrocytes / Q000187:drug effects / Q000502:physiology*; D002118:Calcium / Q000494:pharmacology; D002460:Cell Line; D005910:Glioma / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D008264:Macrophages / Q000502:physiology; D008564:Membrane Potentials; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D011188:Potassium; D002118:Calcium