2005 - Functional in vitro characterization of CR 3394: A novel voltage dependent N-methyl-d-aspartate (NMDA) receptor antagonist
Gabriele Losia, Marco Lanzab, Francesco Makovecb, c, Roberto Artusic, Gianfranco Casellib and Giulia Puiaa, ,
aDepartment of Pharmaceutical Sciences, University of Modena and Reggio Emilia, via Campi 183, 41100 Modena, Italy
bDepartment of Preclinical Pharmacology, Rottapharm S.p.A., Monza (MI), Italy
cDepartment of Chemistry, Rottapharm S.p.A., Monza (MI), Italy
Received 12 May 2005; revised 31 August 2005; accepted 2 September 2005. Available online 19 October 2005.
sciencedirect.com
Abstract
Using the patch-clamp technique, we studied the effect of two novel adamantane derivatives, N-[2-(3,5-dimethyl-1-adamantyl)ethyl] guanidine (CR 3391) and N-[2-(3,5-dimethyl-1-adamantyl) ethyl]acetamidine (CR 3394), on NMDA receptors expressed in cortical neuron cultures. Our data show that CR 3391 and CR 3394 reduce NMDA-evoked currents (IC50 = 1.7 ± 0.6 µM and 6.7 ± 1.5 µM, respectively). This antagonism is non-competitive and is completely reversible. The effect of CR 3394, like that of memantine, was strongly voltage dependent. HEK293 cells expressing NR1a/NR2B recombinant NMDA receptors and immature neurons (DIV 8–9) were more sensitive to CR 3394 antagonism than NR1a/NR2A expressing cells and DIV 15 neurons. CR 3394 also reduced the duration and amplitude of miniature excitatory post-synaptic currents mediated exclusively by NMDA receptors (NMDA-mEPSCs). Both memantine and CR 3394 inhibited NMDA-evoked [3H]norepinephrine release from rat hippocampal slices in a concentration-dependent manner with similar potency. CR 3394, but not memantine, increased cathecholamine resting release at low micromolar concentrations. Moreover, in an in vitro model of neurotoxicity, CR 3394 strongly reduced glutamate- and NMDA-induced neuronal death. Taken together, our data highlight pharmacological features of CR 3394 in vitro that prompt us to further evaluate it as a candidate for the treatment of neurodegenerative disorders.
Keywords: NMDA receptors; NMDA antagonists; Patch-clamp; Neurodegenerative disorders; Electrophysiology
Rottapharm
rotta.com |
