A(1) receptors inhibit glutamate release in rat medullary dorsal horn neurons

作者：Choi In Sun; Cho Jin Hwa; Jang Il Sung^*

来源：NeuroReport, 2011, 22(14): 711-715.

DOI：10.1097/WNR.0b013e32834ab174

• adenosine A(1) receptor
• glutamatergic excitatory postsynaptic currents
• substantia gelatinosa
• trigeminal nucleus

We have investigated the adenosine-mediated presynaptic inhibition of primary afferent-evoked glutamate release in rat substantia gelatinosa neurons of the trigeminal subnucleus caudalis using a conventional whole-cell patch clamp technique. Adenosine reversibly and concentration dependently decreased the amplitude of glutamatergic excitatory postsynaptic currents and increased the paired-pulse ratio, indicating that adenosine acts presynaptically to reduce glutamate release from primary afferents. The adenosine-induced inhibition of excitatory postsynaptic currents was occluded by a selective A(1) receptor antagonist, DPCPX, and was mimicked by a selective A(1) receptor agonist CPA. The results suggest that presynaptic A(1) receptors decrease action potential-dependent glutamate release from trigeminal primary afferents onto medullary dorsal horn neurons, and thus adenosine A(1) receptors could be a potential target for the treatment of pain of orofacial tissues.

• 出版日期2011-10-5