ミヤタ　マリコ   Miyata Mariko   宮田　麻理子    所属   医学部 医学科    職種   教授・基幹分野長
言語種別	英語
発表タイトル	Cortical feedback activity regulates connection pattern of afferent lemniscal synapses in the somatosensory thalamus.
会議名	The 91st Annual Meeting of the Physiological Society of Japan
学会区分	国際学会及び海外の学会
発表形式	ポスター掲示
講演区分	一般
発表者・共同発表者	◎Narushima Madoka, Miyata Mariko
発表年月日	2014/03/16
開催地 （都市, 国名）	Kagoshima Univ., Kagosima, Japan
概要	Plenty of studies revealed synaptic/molecular mechanisms for initial formation and neuronal activity-dependent refinement of synaptic connections in early development. However, mechanisms for subsequent maintenance of once established circuits in matured brain are not fully understood. In the sensory thalamus (VPm and dLGN), the sensory afferent synapses (lemniscal and retinogeniculate (RG) synapses) onto a thalamic neuron are maintained in an experience-dependent manner after developmental synapse elimination. A thalamic neuron receives two kinds of excitatory inputs from afferents and massive feedback corticothalamic (CT) inputs. Thus, the functional linkage between the two inputs may underlie the maintenance of thalamic afferent synapses. Recently we found that type 1 metabotropic glutamate receptor (mGluR1) plays a critical role in the experience-dependent maintenance of RG synapses (Narushima et al., in preparation). Because mGluR1 densely expressed at postsynaptic site of the feedback CT synapses, we hypothesized that cortical activity regulates maintenance of afferent synapses after maturation. Here we report that pharmacological manipulation of cortical activity triggered remodeling of lemniscal synapses. The results support the idea that CT feedback inputs heterosynaptically regulates maintenance of matured mono-innervation of afferent synapses in the sensory thalamus.