ISSN:
1471-4159
Quelle:
Blackwell Publishing Journal Backfiles 1879-2005
Thema:
Medizin
Notizen:
Abstract: A 45Ca2+ influx assay has been used to investigate the pharmacology of stably expressed recombinant human NR1a/NR2A and NR1a/NR2B N-methyl-d-aspartate (NMDA) receptors. Inhibition of glutamate-stimulated 45Ca2+ influx by six glycine-site antagonists and inhibition of glycine-stimulated 45Ca2+ influx by five glutamate-site antagonists revealed no significant differences between affinity values obtained for NR1a/NR2A and NR1a/NR2B receptors. The polyamine site agonist spermine showed differential modulation of glutamate- and glycine-stimulated 45Ca2+ influx for recombinant NMDA receptors, inhibiting and stimulating 45Ca2+ influx into cells expressing NR1a/NR2A receptors (IC50 = 408 µM) and NR1a/NR2B receptors (EC50 = 37.3 µM), respectively. The antagonist ifenprodil was selective for NR1a/NR2B receptors (IC50 = 0.099 µM) compared with NR1a/NR2A receptors (IC50 = 164 µM). The effects of putative polyamine site antagonists, redox agents, ethanol, and Mg2+ and Zn2+ ions were also compared between NR1a/NR2A and NR1a/NR2B receptors. This study demonstrates the use of 45Ca2+ influx as a method for investigating the pharmacology of the numerous modulatory sites that regulate the function of recombinant human NMDA receptors stably expressed in L(tk-) cells.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1046/j.1471-4159.1996.66062589.x
