title: AMPA receptors colocalize with neuropeptide-Y- and galanin-containing, but not with dopamine, neurons of the female rat arcuate nucleus: a semiquantitative immunohistochemical colocalization study.
abstract: It is well established that excitatory amino acid (EAA) neurotransmission is an essential component in the regulation of the gonadotropin-releasing hormone (GnRH) delivery system. However, the morphological interconnection of these systems is not fully understood. The objective of the present study was to determine whether or not alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors--as indicators of aspartate/glutamatergic innervation--are present in the major neuronal populations, such as the neuropeptide-Y-(NPY), galanin- (GAL) and tyrosine-hydroxylase- (TH) containing neurons of the arcuate nucleus (AN) of the female rat. Colocalization experiments using the "mirror" technique demonstrated that: (1) AN neurons containing GluR1 are also immunoreactive (IR) for GluR2/3; (2) 38.32% of AMPA-IR cells contain NPY and 31.72% of AMPA-containing neurons are also IR for GAL; in turn, 79.41% of NPY- and 56.19% of GAL-containing neurons are IR for AMPA receptors; none of the neurons are IR for both AMPA receptors and TH. These data suggest that an excitatory aspartate/glutamatergic input is implicated in the regulation of the examined neuropeptide-containing AN neurons but not in that of TH-IR cells of the same area.
authors.affiliation: Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, CT 06520, USA.
authors.forename: A
authors.initials: A
authors.lastname: Zsarnovszky
authors.forename: T L
authors.initials: TL
authors.lastname: Horvath
authors.forename: F
authors.initials: F
authors.lastname: Naftolin
authors.forename: C
authors.initials: C
authors.lastname: Leranth
mesh_terms: D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000737:chemistry*; D004298:Dopamine / Q000032:analysis; D005260:Female; D019004:Galanin / Q000032:analysis*; D007150:Immunohistochemistry; D009474:Neurons / Q000737:chemistry*; D009478:Neuropeptide Y / Q000032:analysis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018091:Receptors, AMPA / Q000032:analysis*; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis
chemical_list: D004298:Dopamine; D019004:Galanin; D009478:Neuropeptide Y; D018091:Receptors, AMPA; D014446:Tyrosine 3-Monooxygenase; C104723:glutamate receptor ionotropic, AMPA 3; C104722:glutamate receptor ionotropic, AMPA 2