Please cite this article in press as: Lecht, S., et al., Neuroprotective effects of nimodipine and nifedipine in the NGF-differentiated PC12 cells exposed to oxygen-glucose deprivation or trophic withdrawal. Int. J. Dev. Neurosci. (2012), http://dx.doi.org/10.1016/j.ijdevneu.2012.05.007 ARTICLE IN PRESS G Model DN-1692; No. of Pages 5 Int. J. Devl Neuroscience xxx (2012) xxx–xxx Contents lists available at SciVerse ScienceDirect International Journal of Developmental Neuroscience j our na l ho me p age: www.elsevier.com/locate/ijdevneu Neuroprotective effects of nimodipine and nifedipine in the NGF-differentiated PC12 cells exposed to oxygen-glucose deprivation or trophic withdrawal Shimon Lecht a,∗ , Elena Rotfeld b , Hadar Arien-Zakay b , Rinat Tabakman b , Henry Matzner b , Rami Yaka b , Peter I. Lelkes a , Philip Lazarovici b a Integrated Cellular Tissue Engineering & Regenerative Medicine Laboratory, School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, PA 19102, USA b School of Pharmacy Institute for Drug Research, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 91120, Israel a r t i c l e i n f o Article history: Received 26 December 2011 Received in revised form 26 May 2012 Accepted 26 May 2012 Keywords: Nifedipine Nimodipine Oxygen and glucose deprivation PC12 Hypocampal slices Neuroprotection a b s t r a c t The goal of this study was to compare the neuroprotective properties of the l-type Ca 2+ channel block- ers, nimodipine and nifedipine, using nerve growth factor (NGF)-differentiated PC12 neuronal cultures exposed to oxygen-glucose deprivation (OGD) and trophic withdrawal-induced cell death. Nimodipine (1–100 M) conferred 65 ± 13% neuroprotection upon exposure to OGD and 35 ± 6% neuroprotection towards different trophic withdrawal-induced cell death measured by lactate dehydrogenase and cas- pase 3 activities. The time window of nimodipine conferred neuroprotection was detected during the first 5 h but not at longer OGD exposures. Nifedipine (1–100 M), to a lower potency than nimodipine, conferred 30–55 ± 8% neuroprotection towards OGD in PC12 cells and 29 ± 5% in rat hypocampal slices, and 10 ± 3% neuroprotection at 100 M towards trophic withdrawal-induced PC12 cell death. The ability to demonstrate that nimodipine conferred neuroprotection in a narrow therapeutic time-window indi- cates that the OGD PC12 model mimics the in vivo models and therefore suitable for neuroprotective drug discovery and development. © 2012 ISDN. Published by Elsevier Ltd. All rights reserved. 1. Introduction During pathological conditions such as ischemic cerebral injury, the Ca 2+ overload in neurons has detrimental effects leading to brain damage (Auriel and Bornstein, 2010; Zipfel et al., 2000). One strategy to prevent Ca 2+ toxicity was to inhibit its influx into neurons by using Ca 2+ channel blockers (Kobayashi and Mori, 1998). The voltage dependent l-type Ca 2+ channel blockers, belong- ing to the dihydropyridine (DHP) family, widely used for the treatment of hypertension and angina pectoris have been char- acterized as marginal neuroprotectants in a variety of in vitro neuronal ischemic models (Goldberg and Choi, 1993; Pisani et al., 1998; Rahbar-Roshandel et al., 2008) and in vivo animal mod- els of stroke (Babu and Ramanathan, 2011; Horn et al., 2001). Although, the most extensively investigated neuroprotectants in clinical trials of stroke (Ginsberg, 2009) their efficacy was contro- versial (Ahmed et al., 2000; Auriel and Bornstein, 2010; Kaste et al., 1994; Nag et al., 1998; No authors listed, 1990) and it is unknown whether their beneficial effects in the clinics and animal models are due to improvement of blood circulation due to their strong ∗ Corresponding author at: Office No. 14-308, New College Building, 245N 15th Street, Philadelphia, PA 19102, USA. Tel.: +1 215 762 2076; fax: +1 215 762 3150. E-mail address: shimon.lecht@drexel.edu (S. Lecht). vasodilatory effect or to direct action in neurons (Kobayashi and Mori, 1998; Lyden and Wahlgren, 2000; Perlman, 2006). Many fac- tors, including the type of ischemic model, duration and/or severity of the insults (Perlman, 2006), presence or absence of reperfu- sion (Ginsberg, 2009), may explain the failure of translating the pre-clinical strategies to successful clinical trials efficacy, therefore calling for design of more suitable ischemic pharmacological mod- els in vitro to measure neuroprotection and to facilitate novel drug discovery. Nerve growth factor (NGF)-differentiated PC12 sympathetic neuronal cells express voltage dependent l-type Ca 2+ channels (alpha1C and alpha1D sub-units (Colston et al., 1998)) and became widely used neuronal model of oxidative stress (Jiang et al., 2005), trophic factors and serum withdrawal (Ferrari et al., 1993) and oxygen-glucose deprivation (OGD) (Tabakman et al., 2004a, 2005) to study mechanisms of cell death and to develop novel neuropro- tective strategies. The goal of this research was to investigate the neuroprotective effects of the typical DHP drugs nimodipine and nifedipine, upon exposure to either OGD or trophic withdrawal in the PC12 model. We also sought to measure an in vitro correlation between OGD duration and drug-induced neuroprotective effect, since the OGD experimental paradigm used, was composed of a hypoxic and a reoxygenation/reperfusion phase, thus better represents the stroke insult. 0736-5748/$36.00 © 2012 ISDN. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ijdevneu.2012.05.007