title: Glutamate co-transmission from developing medial nucleus of the trapezoid body--lateral superior olive synapses is cochlear dependent in kanamycin-treated rats.
abstract: Cochlear dependency of glutamate co-transmission at the medial nucleus of the trapezoid body (MNTB)--the lateral superior olive (LSO) synapses was investigated using developing rats treated with high dose kanamycin. Rats were treated with kanamycin from postnatal day (P) 3 to P8. A scanning electron microscopic study on P9 demonstrated partial cochlear hair cell damage. A whole cell voltage clamp experiment demonstrated the increased glutamatergic portion of postsynaptic currents (PSCs) elicited by MNTB stimulation in P9-P11 kanamycin-treated rats. The enhanced VGLUT3 immunoreactivities (IRs) in kanamycin-treated rats and asymmetric VGLUT3 IRs in the LSO of unilaterally cochlear ablated rats supported the electrophysiologic data. Taken together, it is concluded that glutamate co-transmission is cochlear-dependent and enhanced glutamate co-transmission in kanamycin-treated rats is induced by partial cochlear damage.
authors.affiliation: Institute of Tissue Regeneration Engineering (ITREN), Dankook University, San 29, Anseo-dong, Cheonan-si, Chungnam 330-714, Republic of Korea.
authors.forename: Jae Ho
authors.initials: JH
authors.lastname: Lee
authors.forename: Jonu
authors.initials: J
authors.lastname: Pradhan
authors.forename: Dhiraj
authors.initials: D
authors.lastname: Maskey
authors.forename: Ki Sup
authors.initials: KS
authors.lastname: Park
authors.forename: Sung Hwa
authors.initials: SH
authors.lastname: Hong
authors.forename: Myung-Whan
authors.initials: MW
authors.lastname: Suh
authors.forename: Myeung Ju
authors.initials: MJ
authors.lastname: Kim
authors.forename: Seung Cheol
authors.initials: SC
authors.lastname: Ahn
mesh_terms: D000818:Animals; D003051:Cochlea / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism*; D006198:Hair Cells, Auditory / Q000187:drug effects / Q000378:metabolism*; D007612:Kanamycin / Q000494:pharmacology; D009847:Olivary Nucleus / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017470:Receptors, Glutamate / Q000378:metabolism; D013569:Synapses / Q000187:drug effects / Q000378:metabolism*; D050496:Vesicular Glutamate Transport Proteins / Q000378:metabolism
chemical_list: D017470:Receptors, Glutamate; C482103:Slc17a8 protein, rat; D050496:Vesicular Glutamate Transport Proteins; D018698:Glutamic Acid; D007612:Kanamycin