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在新鲜分离大鼠背根神经节（DRG）的56个细胞标本上，应用全细胞膜片箝技术进行记录。胞外加缓激肽（BK，10－6～10－4mol/L）引起的DRG细胞膜反应结果如下：（1）71.4％的细胞为内向电流，其电流反应的幅值具有明显的浓度依赖性；（2）12．5％的细胞为外向电流；（3）16.1％的细胞未引起可检测的膜反应。单独给予ATP（10－6～10－3mol/L）在大多数受检细胞（54/56）引起一浓度依赖性内向电流，并有明显的去敏感现象。预加BK30S后再加ATP，则ATP激活电流明显增强，其电流幅值的增强作用依赖于BK及ATP浓度。BK对ATP激活电流的增强作用以增强其峰电流为主，对稳态部分增强不明显。实验观察了BK增强作用的时程，在检测的4例细胞中发现BK均于预加30s后起效，作用持续20min以上。本文结果提示：BK在初级感觉神经元水平对ATP引起的兴奋性反应可能起到一种易化作用。
Whole-cell patch-clamp technique was used to record 56 freshly isolated rat DRG neurons. The results of DRG cell membrane reaction induced by extracellular bradykinin (BK, 10-6 ~ 10-4mol / L) were as follows: (1) 71.4% of the cells were inward current and the amplitude of current response was significantly concentration dependent; (2) 12.5% of the cells were outward currents; (3) 16.1% of the cells did not elicit a detectable membrane reaction. ATP alone (10-6 ~ 10-3mol / L) induced a concentration-dependent inward current in most of the tested cells (54/56) with significant desensitization. Pretreatment BK30S plus ATP, the ATP activation current was significantly enhanced, the current amplitude enhancement depends on the concentration of BK and ATP. The enhancement effect of BK on ATP-activated current to enhance its peak current was not obvious for steady state. The duration of BK enhancement was observed experimentally. BK in 4 tested cells was found to be effective after being pre-applied for 30 seconds, and the effect continued for more than 20 minutes. Our results suggest that BK may play an facilitation role in the excitatory response to ATP induced by primary sensory neurons.