Biomaterial Database

Responses of substantia nigra pars reticulata neurons to intrastriatal D1 and D2 dopaminergic agonist injections in the rat. 1996

D Akkal, and P Burbaud, and J Audin, and B Bioulac

Laboratoire de Neurophysiologie-UMR CNRS 5543, Université de Bordeaux II, France.

Extracellular neuronal recordings were performed in the substantia nigra pars reticulata (SNr) of normal and 6-hydroxydopamine (6-OHDA)-lesioned rats during intrastriatal D1 and D2 dopaminergic-agonist injections. Three types of responses were observed, inhibition, excitation and/or regularization of neuronal discharge patterns. In normal rats, variable responses were observed after D2 injections and a predominance of inhibition after D1 injections. In lesioned rats, the percentage of neurons inhibited and that of neurons regularized increased following D2 injections. During sequential intrastriatal D1 and D2 agonist injections, a response to both dopaminergic agents was observed in 22.5% and 55.5% of SNr neurons in normal and lesioned rats, respectively. Our data suggests that the physiological relevance of direct and indirect pathways convergence upon a given SNr target neuron depends on their respective synaptic weight, the influence of surrounding SNr neurons and the state of dopamine depletion.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008845	Microinjections	The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.	Microinjection
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D004594	Electrophysiology	The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
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
D013378	Substantia Nigra	The black substance in the ventral midbrain or the nucleus of cells containing the black substance. These cells produce DOPAMINE, an important neurotransmitter in regulation of the sensorimotor system and mood. The dark colored MELANIN is a by-product of dopamine synthesis.	Nigra, Substantia,Nigras, Substantia,Substantia Nigras
D015647	2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine	A selective D1 dopamine receptor agonist used primarily as a research tool.	1H-3-Benzazepine-7,8-diol, 2,3,4,5-tetrahydro-1-phenyl-,R-SK&F 38393,SK&F-38393,SKF 38393-A,SKF-38393,SKF38393,RSK&F 38393,SK&F 38393,SK&F38393,SKF 38393,SKF 38393 A,SKF 38393A
D016627	Oxidopamine	A neurotransmitter analogue that depletes noradrenergic stores in nerve endings and induces a reduction of dopamine levels in the brain. Its mechanism of action is related to the production of cytolytic free-radicals.	6-Hydroxydopamine,6-OHDA,Oxidopamine Hydrobromide,Oxidopamine Hydrochloride,6 Hydroxydopamine,Hydrobromide, Oxidopamine,Hydrochloride, Oxidopamine
D017072	Neostriatum	The phylogenetically newer part of the CORPUS STRIATUM consisting of the CAUDATE NUCLEUS and PUTAMEN. It is often called simply the striatum.
D017208	Rats, Wistar	A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.	Wistar Rat,Rat, Wistar,Wistar Rats