CAJ | 학술논문

本文在培养的大鼠三叉神经节(trigeminal ganglion,TG)神经元上采用全细胞膜片钳技术,探讨大麻素对大鼠TG神经元ATP激活电流(ATP-activated currents,IATP)的影响.结果显示:(1)胞外给予ATP,大部分受检细胞(67/75,89.33%)可记录到一个内向电流,且具有剂量依赖性.该电流可被P2X嘌呤受体特异性拮抗剂PPADS所阻断.(2)预加WIN55212-2[大麻素受体1(cannabinoid receptor 1,CB1受体)激动剂]可对IATP产生抑制作用,此作用呈剂量依赖性,并可被CB1受体特异性拮抗剂AM281阻断.预加不同浓度的WIN55212-2(1x10-13、1x10-12、1x10-11、1x10-10、1x10-9和1x10-8mol/L)对IATP(1x10-4mol/L ATP)的抑制作用分别为(8.14±3.14)%、(20.11±2.72)%、(46.62±3.51)%、(72.16±5.64)%、(80.21±2.80)%和(80.59±3.55)%.(3)预加WIN55212-2后IATP的浓度-反应曲线明显下移;最大反应浓度时的IATP幅值减小了(58.02±4.21)%,而阈值基本不变;预加WIN55212.2前后曲线的EC50值非常接近(1.15x10-4mol/L vs 1.27x10-4 mol/L).(4)预加forskolin[腺苷酸环化酶(adenylyl cyclase,AC)激动剂]或8-Br-cAMP可以逆转WIN55212-2对IATP的抑制作用.以上结果表明,大麻素可能作用于CB1受体,通过抑制AC-cAMP-PKA途径发挥对IATP的抑制作用.
본문재배양적대서삼차신경절(trigeminal ganglion,TG)신경원상채용전세포막편겸기술,탐토대마소대대서TG신경원ATP격활전류(ATP-activated currents,IATP)적영향.결과현시:(1)포외급여ATP,대부분수검세포(67/75,89.33%)가기록도일개내향전류,차구유제량의뢰성.해전류가피P2X표령수체특이성길항제PPADS소조단.(2)예가WIN55212-2[대마소수체1(cannabinoid receptor 1,CB1수체)격동제]가대IATP산생억제작용,차작용정제량의뢰성,병가피CB1수체특이성길항제AM281조단.예가불동농도적WIN55212-2(1x10-13、1x10-12、1x10-11、1x10-10、1x10-9화1x10-8mol/L)대IATP(1x10-4mol/L ATP)적억제작용분별위(8.14±3.14)%、(20.11±2.72)%、(46.62±3.51)%、(72.16±5.64)%、(80.21±2.80)%화(80.59±3.55)%.(3)예가WIN55212-2후IATP적농도-반응곡선명현하이;최대반응농도시적IATP폭치감소료(58.02±4.21)%,이역치기본불변;예가WIN55212.2전후곡선적EC50치비상접근(1.15x10-4mol/L vs 1.27x10-4 mol/L).(4)예가forskolin[선감산배화매(adenylyl cyclase,AC)격동제]혹8-Br-cAMP가이역전WIN55212-2대IATP적억제작용.이상결과표명,대마소가능작용우CB1수체,통과억제AC-cAMP-PKA도경발휘대IATP적억제작용.
The present study aimed to investigate whether cannabinoids could modulate the response mediated by ATP receptor (P2X purinoceptor).Whole-cell patch-clamp recording was performed on cultured rat trigeminal ganglionic (TG)neurons.The majority of TG neurons were sensitive to ATP(67/75,89.33%).Extracellular pretreatment with WIN55212-2,a cannabinoid receptor 1(CB1 receptor)agonist,reduced ATP-activated current(IATP)significantly.This inhibitory effect was concentration-dependent and was blocked by AM281,a specific CB1 receptor antagonist.Pretreatment with WIN55212-2 at 1x10-13,1x10-12,1x10-11,1x10-10,1×10-9 and 1x10-8mol/L reduced IATP(induced by 1x10-4mol/L ATP)by(8.14±3.14)%,(20.11±2.72)%,(46.62±3.51)%,(72.16±5.64)%,(80.21±2.80)% and (80.59±3.55)%,respectively.The concentration-response curves for IATP pretreated with and without WIN55212-2showed that WIN55212-2 shifted the curve downward,and decreased the maximal amplitude of IATP by(58.02±4.21)%.But the threshold value and EC50(1.15x10-4 mol/L vs 1.27x10-4 mol/L)remained unchanged.The inhibition of IATP by WIN55212-2 was reversed by AM281,suggesting that the inhibition was mediated via the CB1 receptor.Pretreatment with forskolin [an agonist of adenylyl cyclase (AC)] or 8-Br-cAMP reversed the inhibition of IATP by WIN55212-2.These results suggest that the inhibitory effect of cannabinoids on IATP is mediated via the CB1 receptors,that lead to inhibition of the AC-cAMP-PKA signaling pathway.