{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,10]],"date-time":"2026-10-10T13:52:10Z","timestamp":1791640330713,"version":"4.3.4"},"reference-count":53,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2021,9,25]],"date-time":"2021-09-25T00:00:00Z","timestamp":1632528000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012190","name":"Ministry of Science and Higher Education of the Russian Federation","doi-asserted-by":"publisher","award":["AAAA-A20-120101390067-0"],"award-info":[{"award-number":["AAAA-A20-120101390067-0"]}],"id":[{"id":"10.13039\/501100012190","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Epileptic discharges manifest in individual neurons as abnormal membrane potential fluctuations called paroxysmal depolarization shift (PDS). PDSs can combine into clusters that are accompanied by synchronous oscillations of the intracellular Ca2+ concentration ([Ca2+]i) in neurons. Here, we investigate the contribution of L-type voltage-gated calcium channels (VGCC) to epileptiform activity induced in cultured hippocampal neurons by GABA(A)R antagonist, bicuculline. Using KCl-induced depolarization, we determined the optimal effective doses of the blockers. Dihydropyridines (nifedipine and isradipine) at concentrations \u2264 10 \u03bcM demonstrate greater selectivity than the blockers from other groups (phenylalkylamines and benzothiazepines). However, high doses of dihydropyridines evoke an irreversible increase in [Ca2+]i in neurons and astrocytes. In turn, verapamil and diltiazem selectively block L-type VGCC in the range of 1\u201310 \u03bcM, whereas high doses of these drugs block other types of VGCC. We show that L-type VGCC blockade decreases the half-width and amplitude of bicuculline-induced [Ca2+]i oscillations. We also observe a decrease in the number of PDSs in a cluster and cluster duration. However, the pattern of individual PDSs and the frequency of the cluster occurrence change insignificantly. Thus, our results demonstrate that L-type VGCC contributes to maintaining the required [Ca2+]i level during oscillations, which appears to determine the number of PDSs in the cluster.<\/jats:p>","DOI":"10.3390\/ijms221910342","type":"journal-article","created":{"date-parts":[[2021,9,27]],"date-time":"2021-09-27T04:55:33Z","timestamp":1632718533000},"page":"10342","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Role of L-Type Voltage-Gated Calcium Channels in Epileptiform Activity of Neurons"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4903-5963","authenticated-orcid":false,"given":"Denis P.","family":"Laryushkin","sequence":"first","affiliation":[{"name":"Institute of Theoretical and Experimental Biophysics of the Russian Academy of Sciences, 142290 Pushchino, Russia"},{"name":"Federal Research Center \u201cPushchino Scientific Center for Biological Research of the Russian Academy of Sciences\u201d, Institute of Cell Biophysics of the Russian Academy of Sciences, 142290 Pushchino, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sergei A.","family":"Maiorov","sequence":"additional","affiliation":[{"name":"Federal Research Center \u201cPushchino Scientific Center for Biological Research of the Russian Academy of Sciences\u201d, Institute of Cell Biophysics of the Russian Academy of Sciences, 142290 Pushchino, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1990-3803","authenticated-orcid":false,"given":"Valery P.","family":"Zinchenko","sequence":"additional","affiliation":[{"name":"Federal Research Center \u201cPushchino Scientific Center for Biological Research of the Russian Academy of Sciences\u201d, Institute of Cell Biophysics of the Russian Academy of Sciences, 142290 Pushchino, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4221-5344","authenticated-orcid":false,"given":"Sergei G.","family":"Gaidin","sequence":"additional","affiliation":[{"name":"Federal Research Center \u201cPushchino Scientific Center for Biological Research of the Russian Academy of Sciences\u201d, Institute of Cell Biophysics of the Russian Academy of Sciences, 142290 Pushchino, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Artem M.","family":"Kosenkov","sequence":"additional","affiliation":[{"name":"Federal Research Center \u201cPushchino Scientific Center for Biological Research of the Russian Academy of Sciences\u201d, Institute of Cell Biophysics of the Russian Academy of Sciences, 142290 Pushchino, Russia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"883","DOI":"10.1111\/j.1528-1167.2009.02481.x","article-title":"Estimation of the burden of active and life-time epilepsy: A meta-analytic approach","volume":"51","author":"Ngugi","year":"2010","journal-title":"Epilepsia"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Shao, L.-R., Habela, C.W., and Stafstrom, C.E. 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