title: L-type calcium channels mediate synchronized spontaneous Ca2+spikes in cultured cortical networks.
abstract: We have detected synchronized spontaneous Ca2+spikes in cultured cortical networks in the presence of Mg2+. The synchronized spontaneous Ca2+spikes are synaptically driven, as it is blocked by tetrodotoxin (TTX), and by the glutamate receptor antagonist CNQX/APV. The oscillatory activity is not influenced by GABA<inf>A</inf>receptor antagonist picrotoxin, suggesting that they entirely rely on glutamatergic neurotransmission. We have also found that these Ca2+spikes are dependent on an influx of extracellular Ca2+but are independent of mobilization of Ca2+from intracellular Ca2+stores. Ca2+entry occurred primarily through L-type voltage-gated calcium channels (VGCCs), since nifedipine completely blocked these Ca2+spikes.
authors.affiliation: Key Laboratory of Biomedical Photonics of Ministry of Education, Huazhong University of Science and Technology, Wuhan 430074, P.R. China (e-mail: hjytzx@163.com).
authors.forename: Jun
authors.initials: J
authors.lastname: He
authors.forename: Wei
authors.initials: W
authors.lastname: Zhou
authors.forename: Shaoqun
authors.initials: S
authors.lastname: Zeng
authors.forename: Qingming
authors.initials: Q
authors.lastname: Luo