Fig. 5. A blockade of gap junctions decreases the viability of neural progenitors. Single cell suspensions of striatal progenitors were grown for 3 days in the presence of either the uncoupling agent 18-ß-glycyrrhetinic acid (ßGA) or its inactive analog glycyrrhyzic acid (GZA). The size of neurospheres was reduced by ßGA (C,D) in comparison with that of GZA-treated ones (A,B). This effect was reversible (rev), as the size of floating neurospheres pre-treated with ßGA (G-H) was similar to that of GZA-treated cultures (E-F) following an additional 4 day recovery period, as described in the Materials and Methods. Bar, 300 µM (A-D); 780 µM (E-H).