title: Retrograde HRP tracing combined with a pharmacohistochemical method for GABA transaminase for the identification of presumptive GABAergic projections to the habenula.
abstract: A pharmacohistochemical method for GABA-transaminase (GABA-T), the key enzyme for GABA metabolism, has been combined with retrograde tracing by horseradish peroxidase, to a study of projections to the lateral habenula. The results indicate that projections to the lateral habenula arise from both GABA-T intensive and non-GABA-T staining cells in the rostral entopeduncular nucleus and the lateral hypothalamus suggesting that these projections contain GABAergic elements, as indicated by previous work, but also involve other neurotransmitters. A few GABA-T intensive cells in the lateral preoptic area were also found to project to the lateral habenula by this double staining technique.
mesh_terms: D000612:4-Aminobutyrate Transaminase / Q000378:metabolism*; D000818:Animals; D006651:Histocytochemistry / Q000379:methods; D006735:Horseradish Peroxidase; D008297:Male; D009434:Neural Pathways / Q000033:anatomy & histology; D009445:Neuroanatomy / Q000379:methods; D051381:Rats; D009435:Synaptic Transmission; D013788:Thalamus / Q000033:anatomy & histology* / Q000201:enzymology / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
chemical_list: D005680:gamma-Aminobutyric Acid; D006735:Horseradish Peroxidase; D000612:4-Aminobutyrate Transaminase