Biomaterial Database

Anatomical and electrophysiological evidence for an excitatory amino acid pathway from the thalamic mediodorsal nucleus to the prefrontal cortex in the rat. 1994

S Pirot, and T M Jay, and J Glowinski, and A M Thierry

INSERM U 114, Collège de France, Paris.

This study was undertaken to identify the neurotransmitter of the projection from the thalamic mediodorsal nucleus (MD) to the prefrontal cortex (PFC) using both retrograde transport of D-[3H]aspartate and electrophysiological approaches in the rat. Unilateral microinjections of D-[3H]aspartate performed into the prelimbic area of the PFC resulted in dense labelling of numerous cells in the ipsilateral MD. Excitatory responses were observed in PFC neurons after electrical stimulation of the MD. However, since cortical neurons project to the MD, these excitatory responses could have resulted either from the activation of the MD-PFC pathway and/or from the activation of recurrent collaterals of antidromically driven cortico-thalamic fibres. The conduction time of each of these two reciprocal pathways was determined by antidromic activation. Short latency excitatory responses resulted from activation of the MD-PFC pathway. They were predominantly observed in PFC neurons located in layer III and evoked at low frequency stimulation (0.3-1 Hz). These excitatory responses disappeared or were replaced by longer latency responses when higher frequency stimulations (3-10 Hz) were used. MD-evoked responses were blocked by the iontophoretic application of the AMPA receptor antagonist CNQX into the PFC. These results indicate that the MD-PFC pathway utilizes glutamate and/or aspartate as the neurotransmitter and that its activation induces excitation in PFC neurons through AMPA receptors. Even though the local application of the NMDA receptor antagonist APV was ineffective, a contribution of these receptors in MD-PFC transmission cannot be excluded.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009431	Neural Conduction	The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.	Nerve Conduction,Conduction, Nerve,Conduction, Neural,Conductions, Nerve,Conductions, Neural,Nerve Conductions,Neural Conductions
D009434	Neural Pathways	Neural tracts connecting one part of the nervous system with another.	Neural Interconnections,Interconnection, Neural,Interconnections, Neural,Neural Interconnection,Neural Pathway,Pathway, Neural,Pathways, Neural
D011930	Reaction Time	The time from the onset of a stimulus until a response is observed.	Response Latency,Response Speed,Response Time,Latency, Response,Reaction Times,Response Latencies,Response Times,Speed, Response,Speeds, Response
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
D000200	Action Potentials	Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.	Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001224	Aspartic Acid	One of the non-essential amino acids commonly occurring in the L-form. It is found in animals and plants, especially in sugar cane and sugar beets. It may be a neurotransmitter.	(+-)-Aspartic Acid,(R,S)-Aspartic Acid,Ammonium Aspartate,Aspartate,Aspartate Magnesium Hydrochloride,Aspartic Acid, Ammonium Salt,Aspartic Acid, Calcium Salt,Aspartic Acid, Dipotassium Salt,Aspartic Acid, Disodium Salt,Aspartic Acid, Hydrobromide,Aspartic Acid, Hydrochloride,Aspartic Acid, Magnesium (1:1) Salt, Hydrochloride, Trihydrate,Aspartic Acid, Magnesium (2:1) Salt,Aspartic Acid, Magnesium-Potassium (2:1:2) Salt,Aspartic Acid, Monopotassium Salt,Aspartic Acid, Monosodium Salt,Aspartic Acid, Potassium Salt,Aspartic Acid, Sodium Salt,Calcium Aspartate,Dipotassium Aspartate,Disodium Aspartate,L-Aspartate,L-Aspartic Acid,Magnesiocard,Magnesium Aspartate,Mg-5-Longoral,Monopotassium Aspartate,Monosodium Aspartate,Potassium Aspartate,Sodium Aspartate,Aspartate, Ammonium,Aspartate, Calcium,Aspartate, Dipotassium,Aspartate, Disodium,Aspartate, Magnesium,Aspartate, Monopotassium,Aspartate, Monosodium,Aspartate, Potassium,Aspartate, Sodium,L Aspartate,L Aspartic Acid
D001370	Axonal Transport	The directed transport of ORGANELLES and molecules along nerve cell AXONS. Transport can be anterograde (from the cell body) or retrograde (toward the cell body). (Alberts et al., Molecular Biology of the Cell, 3d ed, pG3)	Axoplasmic Flow,Axoplasmic Transport,Axoplasmic Streaming,Axonal Transports,Axoplasmic Flows,Axoplasmic Transports,Streaming, Axoplasmic,Transport, Axonal,Transport, Axoplasmic,Transports, Axonal,Transports, Axoplasmic
D013787	Thalamic Nuclei	Several groups of nuclei in the thalamus that serve as the major relay centers for sensory impulses in the brain.	Nuclei, Thalamic