Higher intrinsic network excitability in ventral compared with the dorsal hippocampus is controlled less effectively by GABAB receptors

BMC Neuroscience

Research Article

Costas Papatheodoropoulos¹ 

[1] Laboratory of Physiology, Department of Medicine, School of Health Sciences, University of Patras, Rion, 26504, Patras, Greece;

关键词: Hippocampus;    Septotemporal;    Dorsoventral;    Excitability;    Inhibition;    Disinhibition;    Network;    GABA receptor;    GABA receptor;    NMDA receptor;   

DOI  :  10.1186/s12868-015-0213-z

 received in 2015-08-03, accepted in 2015-11-04,  发布年份 2015

来源: Springer

【 摘 要 】

BackgroundElucidating specializations of the intrinsic neuronal network between the dorsal and the ventral hippocampus is a recently emerging area of research that is expected to help us understand the mechanisms underlying large scale functional diversification along the hippocampus. The aim of this study was to characterize spontaneous network activity between the dorsal and the ventral hippocampus induced under conditions of partial or complete blockade of GABAergic inhibition (i.e. disinhibition).ResultsUsing field recordings from the CA3 and CA1 fields of hippocampal slices from adult rats I found that ventral compared with dorsal hippocampus slices displayed higher propensity for and higher frequency of occurrence of spontaneous field potentials (spfps) at every level of disinhibition. Also NMDA receptor-depended spfps (spfps-nmda) occurred with higher probability more frequently and were larger in the ventral compared with the dorsal hippocampus. Importantly, blockade of GABAB receptors produced a stronger effect in enhancing the probability of generation of spfps and spfps-nmda in the dorsal compared with the ventral hippocampal slices and increased spfps-nmda only in dorsal slices.ConclusionThese results demonstrate a higher intrinsic neuronal excitability of the ventral compared with the dorsal local circuitry with the considerable contribution of NMDA receptors. Furthermore, the GABAB receptors control the total and the NMDA receptor-dependent excitation much less effectively in the ventral part of the hippocampus. It is proposed that NMDA and GABAB receptors significantly contribute to differentiate local network dynamics between the dorsal and the ventral hippocampus with important implications in the information processing performed along the long hippocampal axis.

【 授权许可】

CC BY   
© Papatheodoropoulos. 2015