Tonic adenosine A1 and A2A receptor activation is required for the excitatory action of VIP on synaptic transmission in the CA1 area of the hippocampus
Tonic adenosine A1 and A2A receptor activation is required for the excitatory action of VIP on synaptic transmission in the CA1 area of the hippocampus
复制标题
DOI：
10.1016/j.neuropharm.2006.08.003
复制
发表时间：
2007-02-01
影响因子：
4.7
通讯作者：
Sebastiao, A. M.
中科院分区：
文献类型：
--
作者：
Cunha-Reis, D.;Fontinha, B. M.;Sebastiao, A. M.
腺苷可以通过调节其他神经递质的作用来调节突触传递。观察腺苷对VIP增强海马脑片突触传递的影响。当使用腺苷脱氨酶（ADA，1U/ml）去除细胞外内源性腺苷时，1 nM VIP对fEPSP斜率的促进作用（23.3 +/- 1.3%）转化为抑制作用（-12.1 +/- 3.4%）。用1，3-二丙基-8-环戊基黄嘌呤（DPC PX，10 nM）阻断腺苷A（1）受体或用ZM 241385（20 nM）阻断A（2A）受体可减弱VIP的作用。当DPCPX和ZM 241385同时存在时，VIP的作用被消除。在ADA存在的情况下，用N-6-环戊基腺苷（CPA，15 nM）选择性激活A（1）受体或用CGS 21680（10 nM）激活A（2A）受体，部分重新激活VIP对fEPSP的兴奋作用。相比之下，1 nM VIP（19.1 +/- 1.2%）对PS振幅的促进作用在ADA或DPCPX存在下减弱，但ZM 241385未改变。在ADA存在下，CPA完全恢复VIP对PS振幅的影响。总之，VIP促进突触传递到海马锥体细胞树突依赖于内源性腺苷激活A（1）和A（2A）受体。VIP对PS振幅的作用仅依赖于腺苷受体A的激活。这种对腺苷调制的不同敏感性可能是由于VIP对锥体细胞树突和锥体细胞体的作用的不同VIP回路。(c)2006爱思唯尔有限公司保留所有权利。
Adenosine can regulate synaptic transmission through modulation of the action of other neurotransmitters. The influence of adenosine on VIP enhancement of synaptic transmission in hippocampal slices was investigated. Facilitation of fEPSP slope by 1 nM VIP (23.3 +/- 1.3%) was turned into an inhibition (-12.1 +/- 3.4%) when extracellular endogenous adenosine was removed using adenosine deaminase (ADA, 1U/ml). Blockade of adenosine A(1) receptors with 1,3-dipropyl-8-cyclopentylxanthine (DPCPX, 10 nM) or of A(2A) receptors with ZM241385 (20 nM) attenuated the effect of VIP. When both DPCPX and ZM241385 were present the effect of VIP was abolished. In the presence of ADA, selective A(1) receptor activation with N-6-cyclopentyladenosine (CPA, 15 nM) or A(2A) receptor-activation with CGS21680 (10 nM) partially readmitted the excitatory effect of VIP on fEPSPs. In contrast, facilitation of PS amplitude by 1 nM VIP (19.1 +/- 1.2%) was attenuated in the presence of ADA or DPCPX but was not changed by ZM241385. CPA, in the presence of ADA, fully restored the effect of VIP on PS amplitude. In conclusion, VIP facilitation of synaptic transmission to hippocampal pyramidal cell dendrites is dependent on both A(1) and A(2A) receptor activation by endogenous adenosine. VIP effects on PS amplitude are only dependent on A, adenosine receptor activation. This differential sensitivity to adenosine modulation might be due to the different VIP circuits contributing to VIP effects on pyramidal cell dendrites and pyramidal cell bodies. (c) 2006 Elsevier Ltd. All rights reserved.