title: Artemisia santolinifolia enhances glutamatergic neurotransmission in the nucleus of the solitary tract.
abstract: Artemisia extracts have been used as remedies for a variety of maladies related to metabolic and gastrointestinal control. Because the vagal afferent-nucleus of the solitary tract (NST) synapse regulates the same homeostatic functions affected by Artemisia, it is possible that these extracts may have activity at the synaptic level in the NST. Therefore, we evaluated how extracts of three common medicinal Artemisia species, Artemisia santolinifolia (SANT), Artemisia scoparia (SCO), and Artemisia dracunculus L (PMI-5011), modulate the excitability of the glutamatergic vagal afferent-NST synapse. Our in vitro live cell calcium imaging data from prelabeled vagal afferent terminals show that SANT extract is a positive modulator of vagal afferent calcium levels, as the extract significantly increased the calcium signal relative to the time control. Neither SCO nor PMI-5011 extract altered the vagal calcium signals compared to the time control. Furthermore, whole cell voltage-clamp recordings from NST neurons corroborated the vagal terminal calcium data in that SANT extract also significantly increased miniature excitatory postsynaptic current (mEPSC) frequency in NST neurons. These data suggest that SANT extract could be a pharmacologically significant mediator of glutamatergic neurotransmission within the CNS.
authors.affiliation: Laboratory of Autonomic Neuroscience, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA.
authors.forename: Katie M
authors.initials: KM
authors.lastname: Vance
authors.affiliation: Biotech Center, Rutgers University, New Brunswick, NJ 08901, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Ribnicky
authors.affiliation: Laboratory of Autonomic Neuroscience, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA.
authors.forename: Richard C
authors.initials: RC
authors.lastname: Rogers
authors.affiliation: Laboratory of Autonomic Neuroscience, Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808, USA. Electronic address: gerlinda.hermann@pbrc.edu.
authors.forename: Gerlinda E
authors.initials: GE
authors.lastname: Hermann
mesh_terms: D000344:Afferent Pathways; D000818:Animals; D019306:Artemisia / Q000737:chemistry*; D020013:Calcium Signaling; D019706:Excitatory Postsynaptic Potentials; D018698:Glutamic Acid / Q000378:metabolism*; D066298:In Vitro Techniques; D055369:Miniature Postsynaptic Potentials; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D018408:Patch-Clamp Techniques; D010936:Plant Extracts / Q000494:pharmacology*; D017729:Presynaptic Terminals / Q000187:drug effects / Q000502:physiology; D020318:Rats, Long-Evans; D017552:Solitary Nucleus / Q000187:drug effects* / Q000502:physiology; D009435:Synaptic Transmission / Q000187:drug effects*; D014630:Vagus Nerve / Q000502:physiology
chemical_list: D010936:Plant Extracts; D018698:Glutamic Acid
keywords: Botanical; Calcium imaging; Electrophysiology; NST; Presynaptic; mEPSC