Evidence of VTA and LC control of protein synthesis required for the behavioral tagging process.
Several works have shown that the formation of different long-term memories relies on a behavioral tagging process. In other words, to establish a lasting memory, at least two parallel processes must occur: the setting of a learning tag (triggered during learning) that defines where a memory could be stored, and the synthesis of proteins, that once captured at tagged sites will effectively allow the consolidation process to occur. This work focused in studying which brain structures are responsible of controlling the synthesis of those proteins at the brain areas where memory is being stored. It combines electrical activation of the ventral tegmental area (VTA) and/or the locus coeruleus (LC), with local pharmacological interventions and weak and strong behavioral trainings in the inhibitory avoidance and spatial object recognition tasks in rats. The results presented here strongly support the idea that the VTA is a brain structure responsible for regulating the consolidation of memories acting through the D1/D5 dopaminergic receptors of the hippocampus to control the synthesis of new proteins required for this process. Moreover, they provide evidence that the LC may be a second structure with a similar role, acting independently and complementary to the VTA, through the β-adrenergic receptors of the hippocampus.
Neurophysiology of Learning and Memory Research Group, Leibniz-Institute for Neurobiology, Brenneckstr. 6, 39118 Magdeburg, Germany; Instituto de Biología Celular y Neurociencias, Facultad de Medicina, Universidad de Buenos Aires-CONICET, Paraguay 2155, 3° Piso, CP 1121 Buenos Aires, Argentina. Electronic address: dmoncada@fmed.uba.ar.
Diego
D
Moncada
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D000841:Anisomycin / Q000494:pharmacology; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D001552:Benzazepines / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology; D058785:GABA-A Receptor Agonists / Q000494:pharmacology; D008125:Locus Coeruleus / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D000069077:Memory Consolidation / Q000187:drug effects / Q000502:physiology; D009118:Muscimol / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology; D014176:Protein Biosynthesis / Q000187:drug effects / Q000502:physiology*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D021641:Recognition, Psychology / Q000187:drug effects / Q000502:physiology; D017557:Ventral Tegmental Area / Q000187:drug effects / Q000378:metabolism*
D000319:Adrenergic beta-Antagonists; D001552:Benzazepines; D018492:Dopamine Antagonists; D058785:GABA-A Receptor Agonists; D011500:Protein Synthesis Inhibitors; C534628:SCH 23390; D009118:Muscimol; D000841:Anisomycin; D011433:Propranolol
Behavioral tagging; Dopamine; Locus coereleus; Memory; Noradrenaline; Ventral tegmental area