Hanna Ramy L, Kaufman Marc P
Division of Cardiovascular Medicine, Department of Internal Medicine, University of California, Davis 95616, USA.
J Appl Physiol (1985). 2004 Mar;96(3):1166-9. doi: 10.1152/japplphysiol.01020.2003.
The responses of group III and IV triceps surae muscle afferents to intra-arterial injection of alpha,beta-methylene ATP (50 microg/kg) was examined in decerebrate cats. We found that this P2X(3) agonist stimulated only three of 18 group III afferents but 7 of 9 group IV afferents (P < 0.004). The three group III afferents stimulated by alpha,beta-methylene ATP conducted impulses below 4 m/s. Pyridoxal phosphate-6-azophenyl-2',4'-disulfonic acid, a P2-receptor antagonist, prevented the stimulation of these afferents by alpha,beta-methylene ATP. We conclude that P2X(3) agonists stimulate only the slowest conducting group III muscle afferents as well as group IV afferents.
在去大脑猫中，研究了Ⅲ类和Ⅳ类腓肠肌传入纤维对动脉内注射α,β-亚甲基ATP（50微克/千克）的反应。我们发现，这种P2X(3)激动剂仅刺激了18根Ⅲ类传入纤维中的3根，但刺激了9根Ⅳ类传入纤维中的7根（P < 0.004）。被α,β-亚甲基ATP刺激的3根Ⅲ类传入纤维传导冲动的速度低于4米/秒。P2受体拮抗剂磷酸吡哆醛-6-偶氮苯-2',4'-二磺酸可阻止α,β-亚甲基ATP对这些传入纤维的刺激。我们得出结论，P2X(3)激动剂仅刺激传导速度最慢的Ⅲ类肌肉传入纤维以及Ⅳ类传入纤维。
