Influence of extracellular matrix proteins on membrane potentials and excitability in NG108-15 cells

• Published in: Neuroscience letters Vol. 246; no. 1; pp. 9 - 12
• Main Authors: Kowtha, V.C, Bryant, H.J, Pancrazio, J.J, Stenger, D.A
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 17.04.1998; Elsevier
• Subjects: Action Potentials - physiology; Biological and medical sciences; Cell physiology; Collagen; Collagen - physiology; Excitability; Extracellular matrix; Extracellular Matrix Proteins - physiology; Fundamental and applied biological sciences. Psychology; Humans; Hybrid Cells; Laminin; Laminin - physiology; Miscellaneous; Molecular and cellular biology; Neurons - physiology; NG108-15; Peptide Fragments - physiology; Serum-free media; Tumor Cells, Cultured; Excitability; Extracellular matrix; Laminin; NG108-15; Collagen; Serum-free media; Cell line; Electrophysiology; Membrane potential; In vitro; Protein
• ISSN: 0304-3940; 1872-7972
• DOI: 10.1016/S0304-3940(98)00193-1

Previous studies have demonstrated that components of the extracellular matrix can induce neurite extension and cell adhesion in the neuroblastoma×glioma hybrid cell line, NG108-15. Using standard intracellular recording techniques, we examined the resting membrane potential (RMP) and membrane excitability of NG108-15 cells differentiated under serum-free media with representative extracellular matrix (ECM) protein components as the substrate. Surfaces coated with collagen IV and a laminin-1 synthetic peptide induced a significantly ( P<0.05) more hyperpolarized RMP than control polystyrene surfaces. For example, after ≥8 days in culture NG108-15 cells plated on polystyrene exhibited a RMP of −33.2±0.8 mV (mean±SEM, n=158 cells) whereas cells cultured on the laminin-1 peptide C16 and collagen IV showed a RMP of −37.6±0.7 mV ( n=157) and −37.5±1.5 mV ( n=68), respectively. Furthermore, the proportions of cells on ECM substrates showing membrane excitability, i.e. evoked action potentials (APs) and the capability for regular firing, were significantly greater compared to those cells cultured on polystyrene. Among excitable cells cultured on the different substrates, characteristics of the action potentials, such as AP duration, amplitude, and the maximum rate of rise, d V/d t MAX, were examined in detail. While little or no differences were observed between polystyrene and the laminin-1 peptide groups, significant differences in the AP parameters were apparent for collagen IV. For example, d V/d t MAX for polystyrene and the laminin-1 peptide C16 were only 71.7±24.5 V/s ( n=11) and 59.0±8.9 V/s ( n=9), respectively, whereas cells cultured on collagen IV surfaces exhibited a d V/d t MAX reaching 156.1±22.0 V/s ( n=7). These data support a role for ECM components in the maintenance of the RMP and membrane excitability in NG108-15 cells.