PARVALBUMIN-IMMUNOREACTIVE NEURONS IN THE SUBCORTICAL AUDITORY PATHWAY OF THE MONGOLIAN GERBIL (MERIONES-UNGUICULATUS)

The distribution of neurons containing the calcium-binding protein parvalbumin was mapped in the subcortical auditory system of the mongolian gerbil. All nuclei of the auditory pathway expressed numerous neurons, which are imunoreactive with parvalbumin antiserum, with the exception of the meidal geniculate body, which is characterized by parvalbumin-positive neuropil. Soma area measurements of parvalbumin-positive neurons, their distribution patterns within a given auditory nucleus and in some cases also the configuration of their basal dendrites, indicate that parvalbumin-immunoreactivity is not restricted to one morphologically defined neuron population, but rather labels subpopulations of morphologically and/or physiologically defined neuron types. We speculate that parvalbumin-immunoreactive neurons may represent a network of highly active units with fast, highly synchronized firing patterns, which are adapted to rapid and precise processing and analysis of acoustic stimuli.