Nerve growth factor and norepinephrine regulate galanin expression in primary cultures of dorsal root ganglion neurons

Figures & data

Figure 1.  Effects of NGF and/or NE on galanin mRNA expression in primary cultured DRG neurons. Galanin and β-actin mRNA was analyzed by RT-PCR. Lane 1: Normal control (galanin mRNA/β-actin mRNA = 0.3209 ± 0.0433). Lane 2: Exposure of NE (galanin mRNA/β-actin mRNA = 0.4213 ± 0.0198). Lane 3: Exposure of NGF (galanin mRNA/β-actin mRNA = 0.2773 ± 0.0247). Lane 4: Exposure of NGF and NE (galanin mRNA/β-actin mRNA = 0.3692 ± 0.0347). Bar graphs with error bars represent mean ± SD (n = 5). *P < 0.05 versus control, **P < 0.05 versus control, ^#P < 0.05 versus NE, ΔP < 0.0001 versus NGF.

Figure 2.  Effects of NGF and/or NE on galanin peptide expression in primary cultured DRG neurons. Galanin peptide expression was analyzed by Western blot. Lane 1: Normal control (galanin/β-actin = 0.2168 ± 0.0414). Lane 2: Exposure of NE (galanin/β-actin = 0.3454 ± 0.0395). Lane 3: Exposure of NGF (galanin/β-actin = 0.1484 ± 0.0454). Lane 4: Exposure of NGF and NE (galanin/β-actin = 0.2807 ± 0.0441). Bar graphs with error bars represent mean ± SD (n = 5). *P < 0.05 versus control, **P < 0.001 versus control, ^#P < 0.05 versus NE, ΔP < 0.001 versus NGF.

Figure 3.  Dissociated DRG neuronal cultures at 2 days of culture were then treated with NGF and/or NE for an additional 4 days and then immunostained with anti-sera to MAP2. Panel A: Normal control. Panel B: Exposure of NE (10⁻⁴ mol/L). Panel C: Exposure of NGF (10 ng/mL). Panel D: Exposure of NGF (10 ng/mL) and NE (10⁻⁴ mol/L). The number and length of neurites increased in NGF-treated DRG neurons. Scale bar = 20 μm.

Table 1.  Neurite number per neuron after NGF and/or NE treatment (n = 100).

	Neurite number
	Median	Range (xmax-xmin)	Interquartile range (QU-QL)
Control	3	5	3
NE	3	5	2
NGF*^##	3	6	2
NE+NGF*^#	3	6	2

*P < 0.05 versus control, ^#P < 0.05 versus NE, ^##P < 0.01 versus NE.

Q_U, upper quartile; Q_L, lower quartile.

Table 2.  Total neurite length per neuron after NGF and/or NE treatment (n = 100).

	Total neurite length per neuron
	Median (μm)	Range (xmax-xmin) (μm)	Interquartile range (QU-QL) (μm)
Control	186.30	480.64	323.32
NE	182.71	469.07	317.49
NGF*^##	323.81	489.26	248.53
NE+NGF*^#	322.30	484.76	275.22

*P < 0.01 versus control, ^#P < 0.01 versus NE, ^##P < 0.001 versus NE.