Biomaterial Database

Distributions of GABAA, GABAB, and benzodiazepine receptors in the forebrain and midbrain of pigeons. 1994

C L Veenman, and R L Albin, and E K Richfield, and A Reiner

Department of Anatomy and Neurobiology, University of Tennessee, Memphis 38163.

Autoradiographic and immunohistochemical methods were used to study the distributions of GABAA, GABAB and benzodiazepine (BDZ) receptors in the pigeon fore- and midbrain. GABAA, GABAB and BDZ binding sites were found to be abundant although heterogeneously distributed in the telencephalon. The primary sensory areas of the pallium of the avian telencephalon (Wulst and dorsal ventricular ridge) tended to be low in all three binding sites, while the surrounding second order belt regions of the pallium were typically high in all three. Finally, the outermost rind of the pallium (termed the pallium externum by us), which surrounds the belt regions and projects to the striatum of the basal ganglia, was intermediate in all three GABAergic receptors types. Although both GABAA and benzodiazepine receptors were abundant within the basal ganglia, GABAA binding sites were densest in the striatum and BDZ binding sites were densest in the pallidum. Among the brainstem regions receiving GABAergic basal ganglia input, the anterior and posterior nuclei of the ansa lenticularis showed very low levels of all three receptors, while the lateral spiriform nucleus and the ventral tegmental area/substantia nigra complex contained moderate abundance of the three binding sites. The dorsalmost part of the dorsal thalamus (containing nonspecific nuclei) was rich in all three binding sites, while the more ventral part of the dorsal thalamus (containing specific sensory nuclei), the ventral thalamus and the hypothalamus were poor in all three binding sites. The pretectum was also generally poor in all three, although some nuclei displayed higher levels of one or more binding sites. The optic tectum, inferior colliculus, and central gray were rich in all three sites, while among the isthmic nuclei, the parvicellular isthmic nucleus was conspicuously rich in BDZ sites. The results show a strong correlation of the regional abundance of GABA binding sites with previously described distributions of GABAergic fibers and terminals in the avian forebrain and midbrain. The regional distribution of these binding sites is also remarkably similar to that in mammals, indicating a conservative evolution of forebrain and midbrain GABA systems among amniotes.

UI	MeSH Term	Description	Entries
D007150	Immunohistochemistry	Histochemical localization of immunoreactive substances using labeled antibodies as reagents.	Immunocytochemistry,Immunogold Techniques,Immunogold-Silver Techniques,Immunohistocytochemistry,Immunolabeling Techniques,Immunogold Technics,Immunogold-Silver Technics,Immunolabeling Technics,Immunogold Silver Technics,Immunogold Silver Techniques,Immunogold Technic,Immunogold Technique,Immunogold-Silver Technic,Immunogold-Silver Technique,Immunolabeling Technic,Immunolabeling Technique,Technic, Immunogold,Technic, Immunogold-Silver,Technic, Immunolabeling,Technics, Immunogold,Technics, Immunogold-Silver,Technics, Immunolabeling,Technique, Immunogold,Technique, Immunogold-Silver,Technique, Immunolabeling,Techniques, Immunogold,Techniques, Immunogold-Silver,Techniques, Immunolabeling
D008636	Mesencephalon	The middle of the three primitive cerebral vesicles of the embryonic brain. Without further subdivision, midbrain develops into a short, constricted portion connecting the PONS and the DIENCEPHALON. Midbrain contains two major parts, the dorsal TECTUM MESENCEPHALI and the ventral TEGMENTUM MESENCEPHALI, housing components of auditory, visual, and other sensorimoter systems.	Midbrain,Mesencephalons,Midbrains
D010856	Columbidae	Family in the order COLUMBIFORMES, comprised of pigeons or doves. They are BIRDS with short legs, stout bodies, small heads, and slender bills. Some sources call the smaller species doves and the larger pigeons, but the names are interchangeable.	Columba livia,Doves,Pigeons,Domestic Pigeons,Feral Pigeons,Rock Doves,Rock Pigeons,Domestic Pigeon,Dove,Dove, Rock,Doves, Rock,Feral Pigeon,Pigeon,Pigeon, Domestic,Pigeon, Feral,Pigeon, Rock,Pigeons, Domestic,Pigeons, Feral,Pigeons, Rock,Rock Dove,Rock Pigeon
D011963	Receptors, GABA-A	Cell surface proteins which bind GAMMA-AMINOBUTYRIC ACID and contain an integral membrane chloride channel. Each receptor is assembled as a pentamer from a pool of at least 19 different possible subunits. The receptors belong to a superfamily that share a common CYSTEINE loop.	Benzodiazepine-Gaba Receptors,GABA-A Receptors,Receptors, Benzodiazepine,Receptors, Benzodiazepine-GABA,Receptors, Diazepam,Receptors, GABA-Benzodiazepine,Receptors, Muscimol,Benzodiazepine Receptor,Benzodiazepine Receptors,Benzodiazepine-GABA Receptor,Diazepam Receptor,Diazepam Receptors,GABA(A) Receptor,GABA-A Receptor,GABA-A Receptor alpha Subunit,GABA-A Receptor beta Subunit,GABA-A Receptor delta Subunit,GABA-A Receptor epsilon Subunit,GABA-A Receptor gamma Subunit,GABA-A Receptor rho Subunit,GABA-Benzodiazepine Receptor,GABA-Benzodiazepine Receptors,Muscimol Receptor,Muscimol Receptors,delta Subunit, GABA-A Receptor,epsilon Subunit, GABA-A Receptor,gamma-Aminobutyric Acid Subtype A Receptors,Benzodiazepine GABA Receptor,Benzodiazepine Gaba Receptors,GABA A Receptor,GABA A Receptor alpha Subunit,GABA A Receptor beta Subunit,GABA A Receptor delta Subunit,GABA A Receptor epsilon Subunit,GABA A Receptor gamma Subunit,GABA A Receptor rho Subunit,GABA A Receptors,GABA Benzodiazepine Receptor,GABA Benzodiazepine Receptors,Receptor, Benzodiazepine,Receptor, Benzodiazepine-GABA,Receptor, Diazepam,Receptor, GABA-A,Receptor, GABA-Benzodiazepine,Receptor, Muscimol,Receptors, Benzodiazepine GABA,Receptors, GABA A,Receptors, GABA Benzodiazepine,delta Subunit, GABA A Receptor,epsilon Subunit, GABA A Receptor,gamma Aminobutyric Acid Subtype A Receptors
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001345	Autoradiography	The making of a radiograph of an object or tissue by recording on a photographic plate the radiation emitted by radioactive material within the object. (Dorland, 27th ed)	Radioautography
D014018	Tissue Distribution	Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.	Distribution, Tissue,Distributions, Tissue,Tissue Distributions
D016548	Prosencephalon	The anterior of the three primitive cerebral vesicles of the embryonic brain arising from the NEURAL TUBE. It subdivides to form DIENCEPHALON and TELENCEPHALON. (Stedmans Medical Dictionary, 27th ed)	Forebrain,Forebrains
D018079	Receptors, GABA	Cell-surface proteins that bind GAMMA-AMINOBUTYRIC ACID with high affinity and trigger changes that influence the behavior of cells. GABA-A receptors control chloride channels formed by the receptor complex itself. They are blocked by bicuculline and usually have modulatory sites sensitive to benzodiazepines and barbiturates. GABA-B receptors act through G-proteins on several effector systems, are insensitive to bicuculline, and have a high affinity for L-baclofen.	GABA Receptors,Receptors, gamma-Aminobutyric Acid,gamma-Aminobutyric Acid Receptors,GABA Receptor,gamma-Aminobutyric Acid Receptor,Receptor, GABA,Receptor, gamma-Aminobutyric Acid,Receptors, gamma Aminobutyric Acid,gamma Aminobutyric Acid Receptor,gamma Aminobutyric Acid Receptors