CAJ | 학술논문

目的采用电生理记录和行为学观察研究了外周初级传入神经元对单独和联合使用ATP及缓激肽(BK)的反应及其机制.方法在大鼠新鲜分离背根神经节(DRG)神经元标本上应用全细胞膜片钳技术记录ATP激活电流(IATP)以及BK对IATP的调制作用,并结合痛行为实验进行整体行为观察.结果在大鼠新鲜分离的DRG细胞上预加BK后再加ATP,则IATP明显增强,其增强程度依赖于BK的浓度(10-6～10-4 mol/L).预加BK后ATP的量-效曲线上移,其电流最大值与对照相比增加20.75%,而BK预加前后ATP量-效曲线的EC50值非常接近(1.65×10-5 vs 2.0×10-5 mol/L).在大鼠后肢掌底皮下分别注射BK和ATP均引起浓度依赖性的痛行为(抬腿)反应,当联合应用BK(10-6mol/L)和ATP(10-5,10-4 and 10-3 mol/L)时,后爪抬腿时间随ATP浓度的增大而急剧地增强.结论炎性介质BK、ATP等在外周感觉神经末梢疼痛信息的产生、传递和调制方面起着重要的作用.ATP和BK具有协同作用,这种作用是非竞争性的,BK能明显增强IATP.预加BK后,随着ATP浓度的增高所诱导的痛行为反应急剧增加.
목적 채용전생리기록화행위학관찰연구료외주초급전입신경원대단독화연합사용ATP급완격태(BK)적반응급기궤제.방법 재대서신선분리배근신경절(DRG)신경원표본상응용전세포막편겸기술기록ATP격활전류(IATP)이급BK대IATP적조제작용,병결합통행위실험진행정체행위관찰.결과 재대서신선분리적DRG세포상예가BK후재가ATP,칙IATP명현증강,기증강정도의뢰우BK적농도(10-6～10-4 mol/L).예가BK후ATP적량-효곡선상이,기전류최대치여대조상비증가20.75%,이BK예가전후ATP량-효곡선적EC50치비상접근(1.65×10-5 vs 2.0×10-5 mol/L).재대서후지장저피하분별주사BK화ATP균인기농도의뢰성적통행위(태퇴)반응,당연합응용BK(10-6mol/L)화ATP(10-5,10-4 and 10-3 mol/L)시,후조태퇴시간수ATP농도적증대이급극지증강.결론 염성개질BK、ATP등재외주감각신경말소동통신식적산생、전체화조제방면기착중요적작용.ATP화BK구유협동작용,저충작용시비경쟁성적,BK능명현증강IATP.예가BK후,수착ATP농도적증고소유도적통행위반응급극증가.
Objective To explore the responses and mechanisms of peripheral primary afferent neurons to adenosine 5'-triphosphate (ATP) and bradykinin (BK) applied separately or in combination by electrophysiological recording and behavioral observation. Methods The experiments were done on samples of acutely isolated rat dorsal root ganglion (DRG) neurons by the whole-cell patch clamp recording technique, to record ATP-activated current (IATP) and the regulating effect of BK on IATP and to observe the global behavior with pain behavioral experiment. Results ATP added after the pretreatment of BK in the majority of detected cells, IATP would be reinforced significantly, the degree of increment depending on the concentration of BK (BK 10-6 -10-4 mol/L), while the EC50 values of the concentration-response curve with and without pretreatment of BK were very close to each other (1.65×10-5 mol/L vs 2.0×10-5 mol/L). In the behavioral experiment, subcutaneously intraplantar injection of BK and ATP separately in hind limbs of rats both induced concentration-dependent pain behavioral (paw lifting) responses, while the duration of hindpaw lifting was prolonged dramatically with the increase in the ATP concentration, when BK (10-6 mol/L) was injected in combination with ATP (10-5, 10-4 and 10-3 mol/L). Conclusion Inflammatory mediators like BK and ATP etc play an important role in the production, transmission and modulation of pain information in peripheral sensory nerve endings. Both electrophysiological and behavioral experiments demonstrate that there is a synergic effect between ATP and BK, which is thought to be non-competitive. BK may reinforce IATP remarkably, and the pain responses induced by the increment in ATP concentration increase with the existence of BK.