Immunohistochemical localization of N-methyl- d-aspartate and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptor subunits in the substantia nigra pars compacta of the rat

• Published in: Neuroscience Vol. 89; no. 1; pp. 209 - 220
• Main Authors: Albers, D.S., Weiss, S.W., Iadarola, M.J., Standaert, D.G.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.03.1999
• Subjects: Animals; Antibodies; basal ganglia; Basal Ganglia - chemistry; Basal Ganglia - cytology; confocal microscopy; dopamine; Dopamine - physiology; Fluorescent Antibody Technique; glutamate; Glutamic Acid - physiology; Male; Microscopy, Confocal; Neurons - chemistry; Parkinson Disease - metabolism; Parkinson's disease; Rats; Rats, Sprague-Dawley; Receptors, AMPA - agonists; Receptors, AMPA - analysis; Receptors, AMPA - immunology; Receptors, N-Methyl-D-Aspartate - agonists; Receptors, N-Methyl-D-Aspartate - analysis; Receptors, N-Methyl-D-Aspartate - immunology; Substantia Nigra - chemistry; Substantia Nigra - cytology; PBS; Parkinson's disease; basal ganglia; AMPA; GluR; SNpc; FITC; PD; TH; confocal microscopy; NMDA; NMDAR; dopamine; DA; glutamate
• ISSN: 0306-4522; 1873-7544
• DOI: 10.1016/S0306-4522(98)00328-5

Ionotropic glutamate receptors in the substantia nigra pars compacta regulate the activity of dopamine neurons. We have used dual-label immunofluoresence and confocal laser microscopy to study the localization of subunits of two types of ionotropic receptors within the substantia nigra pars compacta of the rat. Immunostaining for N-methyl- d-aspartate receptor 1 and glutamate receptor2/3 was prominent in the soma and proximal dendrites of all tyrosine hydroxylase-immunopositive cells, while only low amounts of N-methyl- d-aspartate receptor 2A and N-methyl- d-aspartate receptor 2B were present. Selective antibodies were used to determine the isoforms of N-methyl- d-aspartate receptor 1 present. Immunostaining for the NI, CI and C2 variably spliced segments of N-methyl- d-aspartate receptor 1 were scarce in the substantia nigra pars compacta, while immunoreactivity for the alternative C2′ terminus of N-methyl- d-aspartate receptor 1 was quite abundant. Staining for glutamate receptor 1 was heterogeneous; about half of the tyrosine hydroxylase immunopositive cells stained intensely, while the other half were immunonegative. The glutamate receptor 1-stained cells were concentrated in the ventral tier of the substantia nigra pars compacta. Glutamate receptor 4 was not found in tyrosine hydroxylase-immunopositive cells within the substantia nigra pars compacta. Together, these data demonstrate that dopaminergic neurons in the substantia nigra pars compacta express primarily glutamate receptor 1, glutamate receptor2/3 and N-methyl- d-aspartate receptor 1 isoforms containing the alternative C2′ terminus.