title: Protein and RNA synthesis-dependent and -independent LTPs in developing rat visual cortex.
abstract: Multiple forms of synaptic potentiation have been described, but their involvement in development versus learning is unknown. To address this, we examined whether long-term potentiation (LTP) in visual cortex requires protein or RNA synthesis using slice preparations. Theta-burst stimulation of white matter induced two distinct types of LTP in layer 4. A slowly developing LTP, preferentially induced in juveniles, was blocked by protein and RNA synthesis inhibitors and was L-type calcium channel dependent. A quickly developing LTP, induced in juveniles and adults, was independent of macromolecular synthesis and required N-methyl-D-aspartate receptor activation. Thus, slow LTP might account for developmental plasticity in visual cortex including the activity-dependent refinement of neural circuitry while fast LTP might underlie the changes in synaptic strength that may participate in visual learning and memory.
authors.affiliation: Department of Physiology, Kyoto Prefectural University of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kurotani
authors.forename: S
authors.initials: S
authors.lastname: Higashi
authors.forename: H
authors.initials: H
authors.lastname: Inokawa
authors.forename: K
authors.initials: K
authors.lastname: Toyama
mesh_terms: D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000096:biosynthesis*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D012313:RNA / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000096:biosynthesis / Q000187:drug effects; D014793:Visual Cortex / Q000254:growth & development* / Q000378:metabolism / Q000502:physiology
chemical_list: D002121:Calcium Channel Blockers; D018691:Excitatory Amino Acid Antagonists; D009419:Nerve Tissue Proteins; D011500:Protein Synthesis Inhibitors; D016194:Receptors, N-Methyl-D-Aspartate; D012313:RNA; D015763:2-Amino-5-phosphonovalerate