Neurotransmitter-specific uptake and retrograde transport of [3H]glycine from the inferior colliculus by ipsilateral projections of the superior olivary complex and nuclei of the lateral lemniscus.
Neurotransmitter-specific uptake and retrograde axonal transport of [3H]glycine were used to identify glycinergic projections to the inferior colliculus in chinchillas and guinea pigs. Six h after injection of [3H]glycine in the inferior colliculus, autoradiographically labeled cells were found ipsilaterally in the ventral nucleus of the lateral lemniscus, the lateral superior olive and the dorsomedial periolivary nucleus. These 3 regions accounted for 95% of the labeled projection neurons, with the remainder scattered elsewhere in the ipsilateral superior olivary complex. No labeled cells were found contralaterally even after survival times as long as 24 h. Retrograde transport of HRP from the inferior colliculus in these same cases confirmed the presence of additional projections that did not accumulate [3H]glycine. These included ipsilateral projections from the medial superior olive and cochlear nucleus and contralateral projections from the inferior colliculus, dorsal nucleus of the lateral lemniscus, lateral superior olive, periolivary nuclei and cochlear nucleus. The results implicate uncrossed projections from the ventral nucleus of the lateral lemniscus, lateral superior olive, and dorsomedial periolivary nucleus as the principal sources of inhibitory glycinergic inputs to the inferior colliculus.
Saint Marie
R L
RL
Department of Anatomy and Neuroscience Program, University of Connecticut Health Center, Farmington 06032.
Baker
R A
RA
D000818:Animals; D001306:Auditory Pathways / Q000033:anatomy & histology* / Q000502:physiology; D001370:Axonal Transport; D002682:Chinchilla; D007839:Functional Laterality; D005998:Glycine / Q000378:metabolism*; D006168:Guinea Pigs; D006735:Horseradish Peroxidase; D007245:Inferior Colliculi / Q000033:anatomy & histology* / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000502:physiology; D018377:Neurotransmitter Agents / Q000378:metabolism*; D009847:Olivary Nucleus / Q000033:anatomy & histology* / Q000502:physiology; D014316:Tritium; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; D014909:Wheat Germ Agglutinins
D018377:Neurotransmitter Agents; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; D014909:Wheat Germ Agglutinins; D014316:Tritium; D006735:Horseradish Peroxidase; D005998:Glycine