Study of the protective effect of calcium channel blockers against neuronal damage induced by glutamate in cultured hippocampal neurons.
BACKGROUND
The aim of this study was to examine the putative protective effect of calcium channel blockers on hippocampal neurons in the experimental model of excitotoxic damage.


METHODS
Seven-day old primary dissociated cultures of rat hippocampal neural cells containing one of the following calcium channel blockers: cinnarizine, flunarizine or nimodipine were exposed to glutamate-induced injury. Quantitative assessments of neuronal injury were accomplished by measuring lactate dehydrogenase (LDH) activity in the media 24 h after exposure to glutamate and by counting and establishing the apoptotic and necrotic cells in flow cytometry with Annexin V-FITC/PI staining.


RESULTS
In our experiment, glutamate induced a 339% elevation of apoptotic cells and a 289% increase of necrotic cells in hippocampal neurons as compared to control cultures without drugs. In cultures containing flunarizine, glutamate-induced cell apoptosis was suppressed by 62% while necrosis showed no significant alternation. Cinnarizine exerted no anti-apoptotic effects on glutamate-injured cultured hippocampal neurons, while nimodipine intensified the apoptotic pathway of cell death and promoted an increase in the number of apoptotic neurons by 26%. When cinnarizine or nimodipine were used, the percentage of necrotic cells was significantly lower when compared with glutamate-injured cultures and it amounted to 44% and 24% for cinnarizine and nimodipine, respectively.


CONCLUSIONS
The obtained results suggest the beneficial anti-apoptotic potential of flunarizine and the anti-necrotic potential of cinnarizine against glutamate-induced death of cultured hippocampal neurons. Nimodipine can protect neurons against necrosis, but has an intensified adverse pro-apoptotic effect on cultured neurons in the experimental model of excitotoxic injury.
Department of Pediatric Neurology and Rehabilitation, Medical University of Bialystok, Białystok, Poland. krsen@wp.pl
Krzysztof
K
Sendrowski
Małgorzata
M
Rusak
Piotr
P
Sobaniec
Elżbieta
E
Iłendo
Milena
M
Dąbrowska
Leszek
L
Boćkowski
Alicja
A
Koput
Wojciech
W
Sobaniec
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D016923:Cell Death / Q000187:drug effects; D002478:Cells, Cultured; D018698:Glutamic Acid / Q000009:adverse effects* / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D009336:Necrosis / Q000188:drug therapy / Q000378:metabolism; D009422:Nervous System Diseases / Q000188:drug therapy* / Q000378:metabolism; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D002121:Calcium Channel Blockers; D018698:Glutamic Acid; D007770:L-Lactate Dehydrogenase