Antisense knockdown of calcium-dependent K+ channels in developing cerebellar Purkinje neurons

Normal developmental upregulation of K-Ca channel activity in cultured rat cerebellar Purkinje neurons was selectively inhibited by antisense oligonuc leotide sequence (3 mu M) targeted against the rslo transcript. The knockdo wn was specific; delayed rectifier and apamin-sensitive K+ channel abundanc es in Purkinje neurons were not affected by rslo antisense. Sense oligonucl eotides (3 mu M), used as a control, had no effect on channel abundance. Qu antitative morphometric analyses of anti-calbindin-labeled Purkinje neurons showed no differences between neurons in control, sense and antisense trea tment groups, and confirmed that the presence of the added oligonucleotide in the sense and antisense treatment conditions had no discernable toxic ef fects on neuronal health, for which neurite outgrowth is a sensitive indica tor. These results confirm the identification of the developmentally regula ted K-Ca channel as the product of the gene rslo in cerebellar Purkinje neu rons. (C) 2000 Elsevier Science B.V. All rights reserved.