Saturday, March 16, 2013

i-Fect™ Delivers you siRNA Payload

Delivering siRNA to Dorsal Root Ganglia to Silence KV Receptors.

Our i-Fect transfection kits continue to be used to optimize delivery in vivo and into hard to transfect cells like primary neurons. In these 2 latest expamples, researchers use i-Fect to deliver siRNA to KV Receptors in Rat DRGs. Knocking down these receptors enable the study of their role in pain modulation: John H. Winston, Sushil K. Sarna. Developmental Origins of Functional Dyspepsia-Like Gastric Hypersensitivity in Rats. Gastroenterology. Volume 144, Issue 3, March 2013, Pages 570–579.e3. dx.doi.org/10.1053/j.gastro.2012.11.001....intrathecal treatment, 2 μg of the appropriate siRNA was mixed (1:5 vol/vol) with i-Fect transfection reagent (Neuromics, Edina, MN); rats received 2 ug siRNA/10 uL/rat/injection...

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.
Tsantoulas C, Zhu L, Shaifta Y, Grist J, Ward JP, Raouf R, Michael GJ, McMahon SB. Sensory neuron downregulation of the Kv9.1 potassium channel subunit mediates neuropathic pain following nerve injury. J Neurosci. 2012 Nov 28;32(48):17502-13. doi: 10.1523/JNEUROSCI.3561-12.2012..."I'd just like to notify you about a recent paper from my team which utilised iFect for in vivo transfection of dorsal root ganglia." Dr. Christoforos Tsantoulas, University of Cambridge...i-Fect-siRNA-mediated knock-down of Kv9.1 in naive rats led to neuropathic pain behaviors...

These add to the many publications referencing use of i-Fect to deliver siRNA. Genes studied include:  DOR, hTERT, The β3 subunit of the Na+,K+-ATPase, rSNSR1, NTS1. NAV1.8, , RANK, Toll-Like Receptors, Kv Recptors, BDNF, Ret, TRPV1, Survivin, Flaviviruses, NOV, Troy β-arrestin, TRPV1 CAV1.2 TLR4 and ASIC.