Monday, November 16, 2015

Kv Channels and Acute to Chronic Pain Transistion

i-Fect TMis a Proven Tool for Gene Manipulation in Studying All Types of Pain

I previously posted on use of our i-Fect Transfection Kit to silence Kv Channels Receptors. This has enabled researchers to study the role of these receptors in vitro and in vivo (see:i-Fect™ Delivers Your siRNA Payload).

Sample Data

Figure: Figures. siRNA-mediated knockdown of Kv1.1 expression in thoracic DRG significantly increased gastric sensitivity in naive adult rats. (A) Western blots showed a significant decrease in Kv1.1 protein in thoracic DRG (T8–T12) after intrathecal treatment with Kv1.1 siRNA but not with control siRNA. siRNA treatment did not alter TrpV1 expression (n = 5 rats each; *P < .01 vs control siRNA). (B) Naive rats treated with Kv1.1 siRNA showed a significant increase in VMR to gastric distention (n = 5 rats each, compared with pretreatment baseline; *P < .05). (C) Treatment with control siRNA had no significant effect on gastric hypersensitivity. (D) Patch clamp recordings from freshly dissociated gastric DRG neurons from FD-like and PND 10 saline-treated littermate controls showed a significant decrease in rheobase in FD-like rats (*P < .05), and (E) a significant increase in the number of action potentials elicited by current injection at 3× the rheobase in gastric DRG neurons from FD-like rats (*P < .05). (F) Sample voltage vs time traces showing action potentials evoked at ×1, ×2, and ×3 rheobase. The patch clamp data were obtained from 16 cells from 5 PND 10 saline control rats and 19 cells from 5 FD-like rats

I am pleased to share with you a new reference detailing how research use i-Fect to optimize and deliver euchromatic histone-lysine N-methyltransferase-2 (G9a) siRNA. This brings the number of publications referencing use of our Transfection Kits to over 45: Geoffroy Laumet, Judit Garriga, Shao-Rui Chen, Yuhao Zhang, De-Pei Li, Trevor M Smith, Yingchun Dong, Jaroslav Jelinek, Matteo Cesaroni, Jean-Pierre Issa & Hui-Lin Pan G9a is essential for epigenetic silencing of K+channel genes in acute-to-chronic pain transition. Nature Neuroscience (2015) doi:10.1038/nn.4165.

The authors report: "Selective knockout of the gene encoding G9a in DRG neurons completely blocked K+ channel silencing and chronic pain development after nerve injury. Remarkably, RNA sequencing analysis revealed that G9a inhibition not only reactivated 40 of 42 silenced genes associated with K+ channels but also normalized 638 genes down- or upregulated by nerve injury."

I will continue to post here new and unique solutions and related referencing for our Gene Expression Analysis Tools.