Figure 8. Expression of several contractile agonist receptors and voltage-dependent Ca²⁺ channels in the collagen gel fibres, as examined by RT-PCR.

RT-PCR was performed as described in Methods using primers specific for muscarinic ACh receptor subtypes m1-m5 (A), endothelin receptor subtypes ET-A and ET-B (B), and L-type (LC) and N-type (NC) Ca²⁺ channels (C). The number of PCR cycles was as follows: m1, × 35; m2, × 35; m3, × 35; m4, × 35; m5, × 35; ET-A, × 30; ET-B, × 30; LC, × 35; NC, × 35. The PCR products were resolved by electrophoresis on 2 % agarose prestained with ethidium bromide. No signal was detected when samples were not reverse transcribed. MW, molecular weight size markers (100 bp DNA ladder). The PCR primers used are given in Table 1.