Expression and functional changes of KCNQ channels in the chronic compression of dorsal root ganglion model

doi:10.3877/cma.j.issn.2095-655X.2017.03.016

Abstract

Abstract:

Objective

To explore the changes of expression and activity of the KCNQ channels in the chronic compression of dorsal root ganglion (CCD) of SD rats model.

Methods

The von Frey filaments were used to assess pain threshold of CCD rats and the control rats.Real-time polymerase chain reaction (PCR) was performed to determine KCNQ2/3/5 mRNA expression of dorsal root ganglion(DRG) tissue.Western blot assay was used to measure KCNQ2/3/5 protein expression.Whole-cell voltage clamp was used to determine M current density of DRG neurons.

Results

CCD rats showed pronounced hyperalgesia behaviors to noxious mechanical stimulation [(4.02±1.06)g, (13.31±1.54)g; t=20.46, P<0.01]. The mRNA and protein levels of KCNQ2/3/5 of DRG tissue notably decreased, followed with the reduction of M current density in DRG neurons of CCD rats [(5.58±1.34)pA/pF, (7.91±1.52)pA/pF; t=4.62, P<0.01]. Intragastric administration of retigabine (KCNQ channels opener) to CCD rats alleviated mechanical hyperalgesia [(6.22±1.52)g, (3.90±1.14)g; t=2.57, P<0.05].

Conclusions

The findings elucidated downregulation of the expression and activity of KCNQ2/3/5 channels in DRG neurons of CCD rats contributes to hyperalgesia.Retigabine exhibits an analgesic effect on mechanical allodynia by increasing the M current of DRG neurons of CCD rats.

Key words: Radiculopathy, KCNQ potassium channels, Ganglia, spinal, Neurons

Lei Li, Yue Zhang. Expression and functional changes of KCNQ channels in the chronic compression of dorsal root ganglion model[J]. Chinese Journal of Diagnostics(Electronic Edition), 2017, 05(03): 205-209.

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Figures/Tables 4

References 20

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组别	例数	0day	2 d	4 d	6 d	8 d	10 d	12 d	14 d
CCD组	20	13.11±1.45	9.85±2.03	6.96±1.89	4.25±1.57	4.17±1.39	3.78±1.12	3.90±1.15	4.02±1.06
假手术组	20	12.53±1.68	13.14±1.32	13.05±1.79	13.26±1.24	12.97±1.93	13.10±1.56	13.22±1.73	13.31±1.54
t值	?	0.85	3.06	9.87	15.38	17.53	19.27	18.91	20.46
P值	?	0.412	0.002	0.000	0.000	0.000	0.000	0.000	0.000

组别	例数	0day	2 d	4 d	6 d	8 d	10 d	12 d	14 d
CCD组	20	13.11±1.45	9.85±2.03	6.96±1.89	4.25±1.57	4.17±1.39	3.78±1.12	3.90±1.15	4.02±1.06
假手术组	20	12.53±1.68	13.14±1.32	13.05±1.79	13.26±1.24	12.97±1.93	13.10±1.56	13.22±1.73	13.31±1.54
t值	?	0.85	3.06	9.87	15.38	17.53	19.27	18.91	20.46
P值	?	0.412	0.002	0.000	0.000	0.000	0.000	0.000	0.000

组别	例数	KCNQ2	KCNQ3	KCNQ5
CCD组	7	0.18±0.06	0.36±0.10	0.40±0.09
假手术组	7	0.25±0.08	0.42±0.11	0.51±0.12
t值	?	3.47	2.85	4.78
P值	?	0.004	0.012	0.000

组别	例数	KCNQ2	KCNQ3	KCNQ5
CCD组	7	0.18±0.06	0.36±0.10	0.40±0.09
假手术组	7	0.25±0.08	0.42±0.11	0.51±0.12
t值	?	3.47	2.85	4.78
P值	?	0.004	0.012	0.000

组别	例数	KCNQ2	KCNQ3	KCNQ5
CCD组	7	0.21±0.06	0.52±0.13	0.24±0.07
假手术组	7	0.37±0.12	0.69±0.15	0.45±0.09
t值	?	2.43	2.64	3.41
P值	?	0.027	0.016	0.003

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