title: Whisker experience-dependent mGluR signaling maintains synaptic strength in the mouse adolescent cortex.
abstract: Sensory experience-dependent plasticity in the somatosensory cortex is a fundamental mechanism of adaptation to the changing environment not only early in the development but also in adolescence and adulthood. Although the mechanisms underlying experience-dependent plasticity during early development have been well documented, the corresponding understanding in the mature cortex is less complete. Here, we investigated the mechanism underlying whisker deprivation-induced synaptic plasticity in the barrel cortex in adolescent mice. Layer 4 (L4) to L2/3 excitatory synapses play a crucial role for whisker experience-dependent plasticity in rodent barrel cortex and whisker deprivation is known to depress synaptic strength at L4-L2/3 synapses in adolescent and adult animals. We found that whisker deprivation for 5 days or longer decreased the presynaptic glutamate release probability at L4-L2/3 synapses in the barrel cortex in adolescent mice. This whisker deprivation-induced depression was restored by daily administration of a positive allosteric modulator of the type 5 metabotropic glutamate receptor (mGluR5). On the other hand, the administration of mGluR5 antagonists reproduced the effect of whisker deprivation in whisker-intact mice. Furthermore, chronic and selective suppression of inositol 1,4,5-trisphosphate (IP3 ) signaling in postsynaptic L2/3 neurons decreased the presynaptic release probability at L4-L2/3 synapses. These findings represent a previously unidentified mechanism of cortical plasticity, namely that whisker experience-dependent mGluR5-IP3 signaling in the postsynaptic neurons maintains presynaptic function in the adolescent barrel cortex.
authors.affiliation: Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Kubota
authors.affiliation: Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.|Department of Physiology, School of Medicine, Faculty of Medicine, Toho University, Ota-ku, Tokyo, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Mikami
authors.affiliation: Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kanemaru
authors.affiliation: Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sekiya
authors.affiliation: Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Okubo
authors.affiliation: Department of Pharmacology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.|Division of Cellular and Molecular Pharmacology, Nihon University School of Medicine, Itabashi-ku, Tokyo, Japan.
authors.forename: Masamitsu
authors.initials: M
authors.lastname: Iino
mesh_terms: D000818:Animals; D018698:Glutamic Acid / Q000378:metabolism; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D051379:Mice; D009473:Neuronal Plasticity; D018094:Receptors, Metabotropic Glutamate / Q000378:metabolism*; D013003:Somatosensory Cortex / Q000254:growth & development* / Q000378:metabolism / Q000502:physiology; D009435:Synaptic Transmission; D014738:Vibrissae / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*
chemical_list: D018094:Receptors, Metabotropic Glutamate; D018698:Glutamic Acid; D015544:Inositol 1,4,5-Trisphosphate
keywords: barrel cortex; experience-dependent plasticity; inositol 1,4,5-trisphosphate; metabotropic glutamate receptor; release probability