Richard L Saint Marie

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The goal of the present study was to provide a comprehensive and quantitative description of neurons immunoreactive for gamma-aminobutyric acid (GABA) in the inferior colliculus (IC) of the cat. Neurons were investigated with two different antisera and two different incubation methods. Free-floating frozen or vibratome-cut sections were incubated either(More)
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,(More)
The aim of the present study was to investigate whether projections from the dorsal cochlear nucleus (DCN) to the anteroventral cochlear nucleus (AVCN) use either of two inhibitory transmitters, glycine or GABA. Retrograde HRP labeling of DCN-to-AVCN projection neurons was combined with postembedding immunocytochemistry in the DCN of guinea pigs. Following(More)
A novel and robust projection from gamma-aminobutyric acid-containing (GABAergic) inferior colliculus neurons to the media] geniculate body (MGB) was discovered in the cat using axoplasmic transport methods combined with immunocytochemistry. This input travels with the classical inferior colliculus projection to the MGB, and it is a direct ascending(More)
Neurons in the lateral superior olive are optimally excited by stimulation of the ipsilateral ear, as are those in the inferior colliculus by stimulation of the contralateral ear. This reversal of ear dominance may result, in part, from distinct crossed excitatory and uncrossed inhibitory pathways ascending from the lateral superior olive. To explore this(More)
The central nucleus of the inferior colliculus is a laminated structure composed of oriented dendrites and similarly oriented afferent fibers that provide a substrate for tonotopic organization. Although inputs from many sources converge in the inferior colliculus, how axons from these sources contribute to the laminar pattern has remained unclear. Here, we(More)
Induction of the cellular fos gene (c-fos) is one of the earliest transcriptional changes observed following neuronal excitation. Although not an activity marker in the strict electrophysiological sense, many neurons in the central nervous system increase their c-fos expression after periods of sustained stimulation at physiological levels of intensity. In(More)
The distribution of GABAergic endings was examined histochemically in the ventral cochlear nucleus (VCN) of the cat using an antibody to glutamate decarboxylase (GAD), the synthetic enzyme for GABA. Immunoreactive (GAD+) endings appeared in all subdivisions of the cat VCN. Each of the principal cell types had a characteristic labeling pattern, based on the(More)
The three nuclei of the cat lateral lemniscus (dorsal, intermediate, and ventral) were distinguished by their immunoreactivities for the putative inhibitory transmitters, gamma-aminobutyric acid (GABA) and glycine. Each nucleus had a distinct pattern of somatic and perisomatic labeling. The dorsal nucleus contained mostly GABA-immunoreactive neurons (85%),(More)
BACKGROUND Sensorimotor gating, as measured by prepulse inhibition of the startle reflex, is deficient in schizophrenia patients, and in rats after specific manipulations of limbic cortico-striato-pallido-thalamic circuitry. For example, prepulse inhibition in rats is disrupted after D1 blockade in the medial prefrontal cortex, and after(More)