Agarose gel electrophoresis of PCR products amplified from rat brain, organ of Corti, and spiral ganglion with specific primers for δ1 (A) or δ2 (B). Lane S, 100 bp standard;lane α9, α9 nicotinic receptor from organ of Corti cDNA; lane OC, organ of Corti; lane SG, spiral ganglion; lane hip, hippocampus; and lane cb, cerebellum. The bands are labeled in units of 100 bp (100 bp DNA ladder standard; Life Technologies).