Fig. 3.

High potassium increases the dendritic localization of TrkB, but not of β-actin, mRNAs in cultured hippocampal neurons. Nonradioactive in situhybridization on cultured hippocampal neurons viewed with Nomarski optics. A, The TrkB riboprobe stains both cell bodies and dendrites. B, On depolarization with 10 mm KCl for 3 hr, the dendritic labeling is detectable at a much greater distance from the cell body. C, The β-actin probe labels the cell bodies under control conditions and (D) after 3 hr depolarization in 10 mm KCl. Scale bar (shown in D): 20 μm forA–D.