A, samples tested were superior cervical ganglia (SCG), coeliac ganglia (CG), superior mesenteric ganglia (SMG) and brain. For the sympathetic ganglia the sample always contained 5 μg of total RNA. A variable amount of total RNA was included in the brain samples as noted. a, elk1 mRNA was expressed in all three sympathetic ganglia. The brain sample contained 5 μg of total RNA. b, elk2 mRNA was not expressed in sympathetic ganglia but was moderately abundant in brain. The brain sample contained 2.5 μg of total RNA. c, eag1 mRNA was expressed at equal levels in all three ganglia and was also expressed in brain. The brain sample contained 14 μg of total RNA. d, eag2 mRNA was barely detectable in the SCG but was expressed in the two prevertebral ganglia, the CG and SMG, as well as in brain. The brain sample contained 14 μg of total RNA. B, elk1 and erg1 mRNA expression in sciatic nerve (SN). Superior cervical ganglia (SCG) RNA served as a positive control. All samples contained 5 μg of total RNA. The cyclophilin gene (cyc) was used as an internal positive control in all experiments to check for sample loss and equal loading.