Kilbride J, Huang L Q, Rowan M J, Anwyl R
Department of Physiology, Trinity College, Dublin, Ireland.
Eur J Pharmacol. 1998 Sep 4;356(2-3):149-57. doi: 10.1016/s0014-2999(98)00526-3.
Electrophysiological studies were carried out on the presynaptic inhibitory action of the group II metabotropic glutamate (mGlu) receptor agonists (+)-2-aminobicyclo[3.1.0]hexane-2-6-dicarboxylic acid (LY354740) and (2S,1'R,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (DCG-IV) in three paths of the rat hippocampus, the medial and lateral perforant path to the dentate gyrus, and the Schaffer collateral/commissural path to CA1. LY354740 caused a dose-dependent reversible inhibition of the field excitatory postsynaptic potential (EPSP) in the medial and lateral perforant paths, with an EC50 of 115 +/- 16 nM and 230 +/- 58 nM, respectively. Maximal inhibition by LY354740 was much greater in the medial path (about 80%) than in the lateral path (about 50%). No inhibition was observed in CA1. A presynaptic inhibition was confirmed by LY354740 inducing dose-dependent changes in paired-pulse depression/facilitation. DCG-IV had a similar action to LY354740, but with a lower potency.
对大鼠海马三条通路，即至齿状回的内侧和外侧穿通通路以及至CA1的Schaffer侧支/连合通路，开展了关于II型代谢型谷氨酸（mGlu）受体激动剂（+）-2-氨基双环[3.1.0]己烷-2,6-二羧酸（LY354740）和（2S,1'R,2'R,3'R）-2-（2',3'-二羧基环丙基）甘氨酸（DCG-IV）的突触前抑制作用的电生理研究。LY354740对内侧和外侧穿通通路中的场兴奋性突触后电位（EPSP）产生剂量依赖性的可逆抑制，其EC50分别为115±16 nM和230±58 nM。LY354740在内侧通路中的最大抑制作用（约80%）远大于外侧通路（约50%）。在CA1中未观察到抑制作用。LY354740诱导成对脉冲抑制/易化的剂量依赖性变化，证实了存在突触前抑制。DCG-IV具有与LY354740相似的作用，但效力较低。
