Retrograde transport of [3H]-GABA by lateral olivocochlear neurons in the rat.

ABSTRACT

Injection of [3H]-gamma aminobutyric acid (GABA) into the perilymphatic space of the rat's inner ear resulted in retrograde labeling of a portion of the small efferent olivocochlear neurons within the lateral superior olivary nucleus (LSO). These cells were of similar size as LSO neurons stained immunohistochemically with antibodies to the GABA synthesizing enzyme glutamic acid decarboxylase (GAD). They were of fusiform shape, but smaller than principal LSO cells, which did not stain for GAD and did not accumulate [3H]-GABA. Other efferent cochlear and vestibular neurons were not labeled.