The selective hyperpolarization-activated cyclic nucleotide-gated（HCN） channel blocker 4-（N-ethyl-N-phenylamino）-1,2-dimethyl-6-（methylamino） pyrimidinium chloride（ZD7288） blocks the induction of long-term pot...The selective hyperpolarization-activated cyclic nucleotide-gated（HCN） channel blocker 4-（N-ethyl-N-phenylamino）-1,2-dimethyl-6-（methylamino） pyrimidinium chloride（ZD7288） blocks the induction of long-term potentiation in the perforant path-CA3 region in rat hippocampus in vivo. To explore the mechanisms underlying the action of ZD7288, we recorded excitatory postsynaptic potentials in perforant path-CA3 synapses in male Sprague-Dawley rats. We measured glutamate content in the hippocampus and in cultured hippocampal neurons using high performance liquid chromatography, and determined intracellular Ca2＋ concentration（[Ca2＋]i） using Fura-2. ZD7288 inhibited the induction and maintenance of long-term potentiation, and these effects were mirrored by the nonspecific HCN channel blocker cesium. ZD7288 also decreased glutamate release in hippocampal tissue and in cultured hippocampal neurons. Furthermore, ZD7288 attenuated glutamate-induced rises in [Ca2＋]i in a concentration-dependent manner and reversed 8-Br-c AMP-mediated facilitation of these glutamate-induced [Ca2＋]i rises. Our results suggest that ZD7288 inhibits hippocampal synaptic plasticity both glutamate release and resultant [Ca2＋]i increases in rat hippocampal neurons.展开更多
AIM: To investigate the effects of ZD 7288, a hyperpolarization-activated cyclic nucleotide-gated (HCN) channel blocker, on rats with chronic visceral pain.
基金supported by grants from the National Natural Science Foundation of China,No.81173038,81001425
文摘The selective hyperpolarization-activated cyclic nucleotide-gated（HCN） channel blocker 4-（N-ethyl-N-phenylamino）-1,2-dimethyl-6-（methylamino） pyrimidinium chloride（ZD7288） blocks the induction of long-term potentiation in the perforant path-CA3 region in rat hippocampus in vivo. To explore the mechanisms underlying the action of ZD7288, we recorded excitatory postsynaptic potentials in perforant path-CA3 synapses in male Sprague-Dawley rats. We measured glutamate content in the hippocampus and in cultured hippocampal neurons using high performance liquid chromatography, and determined intracellular Ca2＋ concentration（[Ca2＋]i） using Fura-2. ZD7288 inhibited the induction and maintenance of long-term potentiation, and these effects were mirrored by the nonspecific HCN channel blocker cesium. ZD7288 also decreased glutamate release in hippocampal tissue and in cultured hippocampal neurons. Furthermore, ZD7288 attenuated glutamate-induced rises in [Ca2＋]i in a concentration-dependent manner and reversed 8-Br-c AMP-mediated facilitation of these glutamate-induced [Ca2＋]i rises. Our results suggest that ZD7288 inhibits hippocampal synaptic plasticity both glutamate release and resultant [Ca2＋]i increases in rat hippocampal neurons.
基金Supported by The Natural Science Fund of Fujian Province,No.C0910595 and No.2012J05053Science Fund and Doctor Initial Fund of FMU,No.09ZD009 and No.2010BS008
文摘AIM: To investigate the effects of ZD 7288, a hyperpolarization-activated cyclic nucleotide-gated (HCN) channel blocker, on rats with chronic visceral pain.
