ABSTRACT
Visceral hypersensitivity is one of the pathogenesis of functional gastrointestinal disorders (FGIDs) including irritable bowel syndrome and functional dyspepsia. In recent years, more and more studies have suggested that the occurrence of gastrointestinal hypersensitivity is related to the changes of neuronal plasticity in the intestinal nervous system or afferent pathway, and potassium channels play a crucial role in controlling neuronal excitability. Lots of studies have shown that decreased expressions or activities of voltage-gated potassium channels, calcium-activated potassium channels, and two-pore domain potassium channels in nociceptors can increase the excitability of neurons, increase visceral pain, and participate in the occurrence of FGIDs. This article reviewed the research progress on relationship between potassium channels and visceral hypersensitivity.
ABSTRACT
Objective To construct rat TRESK gene recombinant adenovirus expression vector.Methods TRESK full-length cDNA was cloned from rat dorsal root ganglion cells and confirmed by RT-PCR and sequencing. pAd/CMV/V5-DEST-TRESK was then constructed under the control of CMV-promotor. DH5α colibacillus was translated and the positive recombinants were subsequently identified by PCR and DNA sequencing. 293T cells were cotransfected and packed to produce adenovirus. Results The titer of virus was tested using Hole-by-dilution titer method. The full length of TRESK from rat dorsal root ganglion cells is 781 bp. It was demonstrated that the DNA sequencing was completely consistent with TRESK sequencing of rat recorded in GeneBank. The PCR amplification of the pAd/CMV/V5-DEST-TRESK gDNA was matched with pAD-GFP blank vector as anticipated. The titer of the concentrated virus was 1.31×109 TU/ml. Conclusion Rat TRESK gene recombinant adenovirus vector is constructed successfully.
ABSTRACT
Objective To investigate the effect of sevoflurane preconditioning on TREK-1 channel expression in hippocampus after focal cerebral ischemia-reperfusion (I/R)in rats and the mechanism.Methods Thirty-six male SD rats weighing 240-280 g were randomly divided into 3 groups(n=12 each):group Ⅰ sham operation (group S),group Ⅱ I/R and group Ⅲ sevoflurane preconditioning (group Sevo).Focal cerebral ischemia was produced by inserting a 4-0 nylon thread with rounded tip into right internal jugular vein.The nylon thread was the nylon thread Wag about 18-20 Innl.The right middle cerebral artery(MCA)Wag occluded for 2 h and then released for 24 h reperfusion.The Sevo group inhaled 2.4% sevoflurane for 30 min at l h before ischemia.Neurological deftcits were assessed and scored at the end of 24 h reperfusion (the higher was the score,the severer was the deficit).The cerebral infarct size was determined by TTC staining and the TREK-1 mRNA in hippocampus by RT-PCR.Results The cerebral infarct size was significantly smaller and the neurological deficit scores were significantly lower in Sevo group than in I/R group.The TREK-1 mBNA expression was significantly up-regulated in Sevo group as compared with I/R group.Conclusion Sevoflurane preconditioning Can protect the brain against I/R injury by activating TREK-1 in hippocampus.