Huang L Q, Rowan M J, Anwyl R
Department of Physiology, Trinity College, Dublin, Ireland.
Neuroreport. 1997 Feb 10;8(3):687-93. doi: 10.1097/00001756-199702100-00022.
The effects of the metabotropic glutamate receptor (mGluR) group II agonist (2S,1'R,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (DCG-IV) and the antagonist 2S,1S',2S'-2-methyl-2-(2'-carboxycyclopropyl)glycine (MCCG) on the induction of long-term potentiation (LTP) and long-term depression (LTD) of the field excitatory postsynaptic potential (epsp) in the dentate gyrus of the rat hippocampus were investigated in vitro. In control media, high frequency stimulation (HFS) consisting of a series of trains of stimuli at 200 Hz induced LTP, and low frequency stimulation (LFS) consisting of 900 stimuli at 1 Hz induced LTD. DCG-IV (50 nM) strongly inhibited the induction of LTP. The block of LTP induction was not caused by a frequency-dependent inhibition of the epsp during HFS, as the epsps evoked during HFS were not altered by DCG-IV. MCCG (500 microM) did not inhibit the induction of LTP, but did prevent the block of LTP by DCG-IV. MCCG (500 microM) strongly inhibited the induction of LTD. DCG-IV (50 nM) did not inhibit LTD induction.
在体外研究了代谢型谷氨酸受体(mGluR)II组激动剂(2S,1'R,2'R,3'R)-2-(2',3'-二羧基环丙基)甘氨酸(DCG-IV)和拮抗剂2S,1S',2S'-2-甲基-2-(2'-羧基环丙基)甘氨酸(MCCG)对大鼠海马齿状回场兴奋性突触后电位(epsp)的长时程增强(LTP)和长时程抑制(LTD)诱导的影响。在对照培养基中,由一系列200Hz刺激串组成的高频刺激(HFS)诱导LTP,由900个1Hz刺激组成的低频刺激(LFS)诱导LTD。DCG-IV(50 nM)强烈抑制LTP的诱导。LTP诱导的阻断不是由HFS期间epsp的频率依赖性抑制引起的,因为HFS期间诱发的epsp不受DCG-IV的影响。MCCG(500 microM)不抑制LTP的诱导,但确实阻止了DCG-IV对LTP的阻断。MCCG(500 microM)强烈抑制LTD的诱导。DCG-IV(50 nM)不抑制LTD的诱导。