title: Ionophoretically applied substance P activates hamster suprachiasmatic nucleus neurons.
abstract: ionophoretic ejection of substance P (SP) activated 31% and suppressed 9% of hamster suprachiasmatic nucleus (SCN) cells in vitro. Hamster SCN cells did not demonstrate variation in sensitivity to SP across the circadian phases tested. SP modulated the response of 47% of hamster SCN cells to the excitatory amino acid (EAA) agonists glutamate and N-methyl-D-aspartate (NMDA). The results indicate that SP can alter both the spontaneous and EAA-evoked firing rate characteristics of hamster SCN neurons.
authors.affiliation: Department of Psychology, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: H D
authors.initials: HD
authors.lastname: Piggins
authors.forename: D J
authors.initials: DJ
authors.lastname: Cutler
authors.forename: B
authors.initials: B
authors.lastname: Rusak
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology; D006224:Cricetinae; D066298:In Vitro Techniques; D007478:Iontophoresis; D008297:Male; D008647:Mesocricetus; D008839:Microelectrodes; D009474:Neurons / Q000187:drug effects*; D013373:Substance P / Q000008:administration & dosage / Q000494:pharmacology*; D013493:Suprachiasmatic Nucleus / Q000166:cytology / Q000187:drug effects / Q000502:physiology*
chemical_list: D013373:Substance P