Activation of Group III mGluRs increases the activity of neurons in area 17 of the cat.
Activation of Group III mGluRs increases the activity of neurons in area 17 of the cat.
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III 组 mGluR 的激活会增加猫第 17 区神经元的活性。
DOI：
10.1017/s095252380219211x
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发表时间：
2002
影响因子：
1.9
通讯作者：
Daw,NW
中科院分区：
文献类型：
--
作者：
Beaver,CJ;Ji,QH;Jin,XT;Daw,NW
通过L（+）-2-氨基-4-膦酰基丁酸（L-AP 4）激活第III组代谢型谷氨酸受体（mGluRs），与来自躯体感觉皮层的体内记录（Wan & Cahusac，1995）相比，对视觉皮层的体外切片制备物（Jin & Daw，1998）具有不同的影响。为了研究组III mGluRs在猫视觉皮层中的作用，对不同年龄的小猫和成年猫的视觉皮层的区域17中的神经元进行体内记录，并检查L-AP 4（100 mM）的离子电渗应用的效果。应用L-AP 4可使神经元自发活动和视觉反应增加，且前者比后者更明显。L-AP 4的作用在3-5周龄时最大，对视觉反应的作用比对自发活动的作用下降得更快。与在大鼠皮层中的工作一致（Jin & Daw，1998），L-AP 4的作用在上层和下层中显著大于在中层中。大鼠视觉皮层切片的全细胞体外记录表明，L-AP 4（50 mM）并没有增加电流注射水平增加引起的尖峰的数量。这些结果证实，L-AP 4在体内增加活性，并与体外结果的差异的原因进行了讨论。
Activation of Group III metabotropic glutamate receptors (mGluRs) by L(+)-2-amino-4-phosphonobutyric acid (L-AP4) has different effects on in vitro slice preparations of visual cortex (Jin & Daw, 1998) as compared with in vivo recordings from somatosensory cortex (Wan & Cahusac, 1995). To investigate the role of Group III mGluRs in the cat visual cortex, in vivo recordings were made of neurons in area 17 of the visual cortex of kittens and adult cats at different ages and the effect of iontophoretic application of L-AP4 (100 mM) was examined. Application of L-AP4 resulted in an increase of the spontaneous activity and visual response of neurons to visual stimulation, the former more than the latter. The effect of L-AP4 was greatest at 3–5 weeks of age with the effect on the visual response declining more rapidly than the effect on spontaneous activity. Consistent with work in rat cortex (Jin & Daw, 1998), the effect of L-AP4 was significantly greater in upper and lower layers than in middle layers. Whole-cell in vitro recordings from slices of rat visual cortex indicated that L-AP4 (50 mM) did not increase the number of spikes elicited by increasing levels of current injections. These results confirm that L-AP4 increases activity in vivo and reasons for the discrepancy with the in vitro results are discussed.