title: Diverse Short-Term Dynamics of Inhibitory Synapses Converging on Striatal Projection Neurons: Differential Changes in a Rodent Model of Parkinson's Disease.
abstract: Most neurons in the striatum are projection neurons (SPNs) which make synapses with each other within distances of approximately 100 µm. About 5% of striatal neurons are GABAergic interneurons whose axons expand hundreds of microns. Short-term synaptic plasticity (STSP) between fast-spiking (FS) interneurons and SPNs and between SPNs has been described with electrophysiological and optogenetic techniques. It is difficult to obtain pair recordings from some classes of interneurons and due to limitations of actual techniques, no other types of STSP have been described on SPNs. Diverse STSPs may reflect differences in presynaptic release machineries. Therefore, we focused the present work on answering two questions: Are there different identifiable classes of STSP between GABAergic synapses on SPNs? And, if so, are synapses exhibiting different classes of STSP differentially affected by dopamine depletion? Whole-cell voltage-clamp recordings on SPNs revealed three classes of STSPs: depressing, facilitating, and biphasic (facilitating-depressing), in response to stimulation trains at 20 Hz, in a constant ionic environment. We then used the 6-hydroxydopamine (6-OHDA) rodent model of Parkinson's disease to show that synapses with different STSPs are differentially affected by dopamine depletion. We propose a general model of STSP that fits all the dynamics found in our recordings.
authors.affiliation: División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Ciudad de México, Mexico.
authors.forename: Janet
authors.initials: J
authors.lastname: Barroso-Flores
authors.affiliation: Departamento de Matemáticas, Facultad de Ciencias, Universidad Nacional Autónoma de México, 04510 Ciudad de México, Mexico.
authors.forename: Marco A
authors.initials: MA
authors.lastname: Herrera-Valdez
authors.affiliation: División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Ciudad de México, Mexico.
authors.forename: Violeta Gisselle
authors.initials: VG
authors.lastname: Lopez-Huerta
authors.affiliation: División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Ciudad de México, Mexico.
authors.forename: Elvira
authors.initials: E
authors.lastname: Galarraga
authors.affiliation: División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, 04510 Ciudad de México, Mexico.
authors.forename: José
authors.initials: J
authors.lastname: Bargas
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D059330:GABAergic Neurons / Q000502:physiology*; D008297:Male; D008959:Models, Neurological; D017072:Neostriatum / Q000166:cytology / Q000502:physiology*; D009473:Neuronal Plasticity; D016627:Oxidopamine; D020734:Parkinsonian Disorders / Q000503:physiopathology; D017208:Rats, Wistar; D013569:Synapses / Q000502:physiology*; D055366:Synaptic Potentials
chemical_list: D016627:Oxidopamine