Constitutive expression of heterologous N-methyl-D-aspartate receptor subunits in rat adrenal medulla.
An RT-PCR analysis revealed constitutive expression of mRNA for N-methyl-D-aspartate (NMDA) receptor (NR)-1, NR-2C, and NR-2D subunits in rat adrenal and pituitary glands, in addition to brain and retina. Constitutive expression of mRNA was detected for the NR-2A subunit in pituitary but not adrenal gland. Although on Western blotting assays adrenal medulla exhibited expression of NR-1 subunit protein without expression of NR-2C and NR-2D subunit proteins, an immunohistochemical investigation clearly showed selective localization of proteins for NR-1, NR-2C, and NR-2D subunits in adrenal medulla but not in adrenal cortex. Prior treatment with different glycosidases invariably resulted in a marked increase in immunoreactivity to the anti-NR-1 antibody in both hippocampus and adrenal medulla. An intraperitoneal injection of a blocker of NMDA receptor channel, but not NMDA itself, led to marked potentiation of DNA binding activity of the transcription factor activator protein-1 in adrenal nuclear extracts 2 hr after administration. These results suggest that heteromeric NMDA receptor channels may be constitutively and functionally expressed with glycosylation of NR-1 subunit under the influence of tonic stimulation by circulating agonists such as L-glutamate in rat adrenal medulla.
Hinoi
Eiichi
E
Department of Molecular Pharmacology, Kanazawa University Faculty of Pharmaceutical Sciences, Kanazawa, Ishikawa, Japan.
Fujimori
Sayumi
S
Nakamura
Yoichi
Y
Balcar
Vladimir J
VJ
Kubo
Keita
K
Ogita
Kiyokazu
K
Yoneda
Yukio
Y
D000313:Adrenal Medulla / Q000378:metabolism*; D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D006031:Glycosylation; D007150:Immunohistochemistry; D007274:Injections, Intraperitoneal; D008297:Male; D016202:N-Methylaspartate / Q000235:genetics; D010870:Pineal Gland / Q000378:metabolism; D010902:Pituitary Gland / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D012160:Retina / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
D016202:N-Methylaspartate; D012333:RNA, Messenger; D016194:Receptors, N-Methyl-D-Aspartate; C409466:NR1 NMDA receptor; C121001:NR2B NMDA receptor