The Distributions of Voltage-Gated K+ current Subtypes in Different Cell Sizes from Adult Mouse Dorsal Root Ganglia
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Voltage-gated K+ (KV) currents play a crucial role in regulating pain by controlling neuronal excitability, and are divided into transient A-type currents (IA) and delayed rectifier currents (IK). The dorsal root ganglion (DRG) neurons are heterogeneous and the subtypes of KV currents display different levels in distinct cell sizes. To observe correlations of the subtypes of KV currents with DRG cell sizes, KV currents were recorded by whole-cell patch clamp in freshly isolated mouse DRG neurons. Results showed that IA occupied a high proportion in KV currents in medium- and large-diameter DRG neurons, whereas IK possessed a larger proportion of KV currents in small-diameter DRG neurons. A lower correlation was found between the proportion of IA or IK in KV currents and cell sizes. These data suggest that IA channels are mainly expressed in medium and large cells and IK channels are predominantly expressed in small cells.
KeywordsVoltage-gated K+ channel Dorsal root ganglia Cell diameter Patch clamp
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The authors declare that they do not have conflict of interests.
- Hayashi Y et al (2009) Bladder hyperactivity and increased excitability of bladder afferent neurons associated with reduced expression of KV1.4 alpha-subunit in rats with cystitis. Am J Physiol Regul Integr Comp Physiol 296:R1661–R1670. https://doi.org/10.1152/ajpregu.91054.2008 CrossRefGoogle Scholar
- Murakami M et al (2004) Antinociceptive effect of different types of calcium channel inhibitors and the distribution of various calcium channel alpha 1 subunits in the dorsal horn of spinal cord in mice. Brain Res 1024:122–129. https://doi.org/10.1016/j.brainres.2004.07.066 CrossRefPubMedGoogle Scholar
- Wang JG, Strong JA, Xie W, Zhang JM (2007) Local inflammation in rat dorsal root ganglion alters excitability and ion currents in small-diameter sensory neurons. Anesthesiology 107:322–332. https://doi.org/10.1097/01.anes.0000270761.99469.a7 CrossRefPubMedPubMedCentralGoogle Scholar
- Xu GY, Winston JH, Shenoy M, Yin H, Pasricha PJ (2006) Enhanced excitability and suppression of A-type K+ current of pancreas-specific afferent neurons in a rat model of chronic pancreatitis. Am J Physiol Gastrointest Liver Physiol 291:G424–G431. https://doi.org/10.1152/ajpgi.00560.2005 CrossRefGoogle Scholar