Quantitative Analysis of Neurotransmitters in the Endings Presynaptic to Vibrissa Afferent Terminals in the Cat Trigeminal Caudal Nucleus

Autor: Yun-Sook Kim, Yong Chul Bae, Cheol-Ju Mun, Sang-Kyoo Paik, Jin-Hyun Cho, Hye-Jeong Bok, Jin-Young Bae, Yeon-Kyung Na
Rok vydání: 2012
Předmět:
Zdroj: Korean Journal of Microscopy. 42:9-16
ISSN: 1225-6773
DOI: 10.9729/am.2012.42.1.009
Popis: The goal of this study was to identify neurotransmitters in endings (p-endings) presynaptic to low-threshold mechanoreceptive vibrissa afferents in the laminae III/IV of cat trigeminal caudal nucleus (Vc). Rapidly-adapting vibrissa afferents were intra-axonally labeled after electrophysiological identification, and postembedding immunogold staining with antisera against -aminobutyric acid (GABA) and glycine was performed, followed by quantitative ultrastructural analysis of p-endings presynaptic to the labeled vibrissa afferent terminals. Sixteen p-endings, which are presynaptic to the HRP-labeled vibrissa afferent terminals, were analyzed in this study: Eight p-endings (50%, 8/16) were immunopositive to GABA but immunonegative to glycine (GABA+ p-ending), and remaining 8 p-endings (50%, 8/16) exhibited immunoreactivity to both GABA and glycine. Bouton volume of the p-endings was not significantly different between the two groups. However, the p-endings differed from each other in relative content of GABA and glycine. These findings suggest that low-threshold mechanoreceptive information conveyed through vibrissa afferent at Vc is presynaptically modulated by GABA and/or glycine, and that degree of presynaptic modulation may differ among each vibrissa afferent terminal.
Databáze: OpenAIRE