title: [3H]-tetrodotoxin binding in neuronal and non-neuronal spinal cord cultures.
abstract: The binding of [3H]-tetrodotoxin [TTX], a sodium channel blocker, was studied in dissociated spinal cord cultures derived from fetal mice. A comparison was made between cultures that consisted of a mixture of neurons and non-neuronal background cells (N + BG) with those that were comprised of only background cells (BG). Specific binding of 1 nM [3H]-TTX was studied in 28-day-old cultures. The IC50 for TTX displacement of [3H]-TTX binding was 10 nM for (N + BG) cultures and 15 nM for (BG). The binding of [3H]-TTX to (N + BG) cultures was approximately 9-fold greater than that observed for the (BG) cultures. During development from day 6 to day 28, the binding of [3H]-TTX in (N + BG) cultures increased about 10-fold per dish or about 30% as expressed as fmol bound per mg protein. Nitrendipine did not displace [3H]-TTX in day 6 (N + BG) cultures, although previous studies indicated that TTX displaced [3H]-nitrendipine binding in developing spinal cord cultures.
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D002478:Cells, Cultured; D007473:Ion Channels / Q000378:metabolism*; D051379:Mice; D009457:Neuroglia / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D009543:Nifedipine / Q000031:analogs & derivatives / Q000378:metabolism; D009568:Nitrendipine; D013116:Spinal Cord / Q000166:cytology / Q000378:metabolism*; D013779:Tetrodotoxin / Q000378:metabolism*
chemical_list: D007473:Ion Channels; D013779:Tetrodotoxin; D009568:Nitrendipine; D009543:Nifedipine