Enkephalin mRNA production by cochlear and vestibular efferent neurons in the gerbil brainstem
Ryan, A.F.; Simmons, D.M.; Watts, A.G.; Swanson, L.W.
Experimental Brain Research 87(2): 259-267
ISSN/ISBN: 0014-4819 PMID: 1769382 DOI: 10.1007/bf00231843
Preproenkephalin mRNA production by efferent neurons projecting to the gerbil inner ear was assessed using combined in situ hybridization and retrograde labeling with fluorescent tracers. Virtually all vestibular efferent neurons were positive for preproenkephalin mRNA. Of the cochlear efferents, one-half of the medial olivocochlear neurons were positive for enkephalin. All lateral olivocochlear neurons were negative for enkephalin. The results suggest that there are two, biochemically distinct subpopulations of medial olivocochlear efferents in the gerbil.