title: Cell-type specificity of mGluR activation in striatal neuronal subtypes.
abstract: The effects of metabotropic glutamate receptor (mGluR) activation were studied in medium spiny neurons and large aspiny (LA) interneurons by means of electrophysiological and optical recordings. DCG-IV and L-SOP, agonists for group II and III mGluRs, respectively, produced a presynaptic inhibitory effect on corticostriatal glutamatergic excitatory postsynaptic potentials (EPSPs) in both spiny and LA cells. Activation of group I mGluRs by the selective agonist 3,5-DHPG produced no effect on membrane properties and glutamatergic transmission in spiny neurons, whereas it did cause a membrane depolarization in LA interneurons coupled to increased input resistance. In combined optical and electrophysiological experiments, in spiny neurons 3,5-DHPG enhanced membrane depolarization and intracellular calcium (Ca2+) levels induced by NMDA applications, but not in LA interneurons. These data suggest the existence of a positive interaction between NMDA and group I mGlu receptors only in medium spiny cells which might, at least partially, account for the differential vulnerability to excitotoxic damage observed in striatal neuronal subtypes.
authors.affiliation: Clinica Neurologica, Dipartimento di Neuroscienze, Università di Roma Tor Vergata, Rome, Italy. Antonio.Pisano@uniroma2.it
authors.forename: A
authors.initials: A
authors.lastname: Pisani
authors.forename: G
authors.initials: G
authors.lastname: Bernardi
authors.forename: P
authors.initials: P
authors.lastname: Bonsi
authors.forename: D
authors.initials: D
authors.lastname: Centonze
authors.forename: P
authors.initials: P
authors.lastname: Giacomini
authors.forename: P
authors.initials: P
authors.lastname: Calabresi
mesh_terms: D000818:Animals; D003342:Corpus Striatum / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials; D005998:Glycine / Q000031:analogs & derivatives / Q000494:pharmacology; D008297:Male; D009474:Neurons / Q000378:metabolism* / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D018094:Receptors, Metabotropic Glutamate / Q000819:agonists* / Q000378:metabolism; D012118:Resorcinols / Q000494:pharmacology
chemical_list: D018690:Excitatory Amino Acid Agonists; D018094:Receptors, Metabotropic Glutamate; D012118:Resorcinols; C079215:3,5-dihydroxyphenylglycine; D005998:Glycine