GABA(B) receptors couple to potassium and calcium channels on identified lateral perforant pathway projection neurons.
GABA(B) receptors couple to potassium and calcium channels on identified lateral perforant pathway projection neurons.
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GABA(B) 受体与已识别的侧穿通路投射神经元上的钾和钙通道偶联。
DOI：
10.1152/jn.2000.83.2.1073
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
Lambert,NA
中科院分区：
文献类型：
--
作者：
Wang,X;Lambert,NA
Activation of presynaptic GABABreceptors inhibits neurotransmitter release at most cortical synapses, at least in part because of inhibition of voltage-gated calcium channels. One synapse where this isnotthe case is the lateral perforant pathway synapse onto dentate granule cells in the hippocampus. The current study was conducted to determine whether the neurons that make these synapses express GABABreceptors that can couple to ion channels. Perforant pathway projection neurons were labeled by injecting retrograde tracer into the dorsal hippocampus. The GABABreceptor agonist baclofen (10 μM) activated inwardly rectifying potassium channels and inhibited currents mediated by voltage-gated calcium channels in retrogradely labeled neurons in layer II of the lateral entorhinal cortex. These effects were reversed by coapplication of the selective GABABreceptor antagonist CGP 55845A (1 μM). Equivalent effects were produced by 100 μM adenosine, which inhibits neurotransmitter release at lateral perforant pathway synapses. The effects of baclofen and adenosine on inward currents were largely occlusive. These results suggest that the absence of GABABreceptor-mediated presynaptic inhibition at lateral perforant pathway synapses is not simply due to a failure to express these receptors and imply that GABABreceptors can either be selectively localized or regulated at terminal versus somatodendritic domains.
