Anesthesiology（华西）：乳化异氟烷增强QX-314的伤害性感觉阻断作用

南粤麻医

来自华西医院麻醉科刘进教授研究团队的文章，研究发现，乳化异氟烷增强QX-314的伤害性感觉阻断作用，其机制与TRPV1通道的激活有关。

Anesthesiology. 2014 Aug;121(2):280-9. doi: 10.1097/ALN.0000000000000236.

Emulsified isoflurane enhances thermal transient receptor potential vanilloid-1 channel activation-mediated sensory/nociceptive blockade by QX-314.

Zhou C1, Liang P, Liu J, Zhang W, Liao D, Chen Y, Chen X, Li T.

Author information

1From the Laboratory of Anesthesia and Critical Care Medicine (C.Z., J.L., W.Z., D.L., Y.C., X.C., T.L.), Department of Anesthesiology (P.L., J.L., W.Z., X.C.), Translational Neuroscience Center, West China Hospital, Sichuan University, Chengdu, Sichuan, P.R. China.

Abstract

BACKGROUND:

QX-314 produces nociceptive blockade, facilitated by permeation through transient receptor potential vanilloid-1 (TRPV1) channels. TRPV1 channel can be activated by noxious heat and sensitized by volatile anesthetics. The authors hypothesized that emulsified isoflurane (EI) could enhance thermal TRPV1 channel activation-mediated sensory/nociceptive blockade by QX-314.

METHODS:

Rats were perineurally injected with QX-314 (Sigma-Aldrich Co. Ltd. Shanghai, China) alone or QX-314 combined with EI, followed by heat exposure on the injection site. The tail-flick and tail-clamping tests were used to assess sensory and nociceptive blockade, respectively; a sciatic nerve block model was used to assess motor and sensory blockade. Effects of EI on thermal activation of TRPV1 channels were evaluated on rat dorsal root ganglia neurons by whole-cell patch-clamp recordings.

RESULTS:

Heat exposure enhanced sensory/nociceptive blockade by QX-314 in rat tails, but not motor blockade in sciatic nerve block model. QX-314 alone or QX-314 + 42°C produced no nociceptive blockade. QX-314 + 48°C produced 100% nociceptive blockade with duration of 12.5 ± 2.0 h (mean ± SEM). By adding 2% EI, QX-314 + 42°C produced 80% nociceptive blockade with duration of 8.1 ± 1.9 h, which was similar to the effect of QX-314 + 46°C (7.7 ± 1.1 h; P = 0.781). The enhancement of heat on sensory/nociceptive blockade of QX-314 was prevented by TRPV1 channel antagonist. The temperature thresholds of TRPV1 channel activation on dorsal root ganglia neurons were significantly reduced by EI.

CONCLUSIONS:

Thermal activation of TRPV1 channels enhanced long-lasting sensory/nociceptive blockade by QX-314 without affecting motor blockade. The addition of EI reduced temperature thresholds for inducing long-lasting sensory/nociceptive blockade due to QX-314.

PMID: 24667830

http://www.ncbi.nlm.nih.gov/pubmed/?term=24667830