title: The paired-pulse index: a measure of hippocampal dentate granule cell modulation.
abstract: This study was undertaken to assess whether the paired-pulse index (PPI) is an effective measure of the modulation of dentate granule cell excitability during normal development. Paired-pulse stimulations of the perforant path were, therefore, used to construct a PPI for 15-, 30-, and 90-day old, freely moving male rats. Significant age-dependent differences in the PPI were obtained. Fifteen-day old rats showed significantly less inhibition at short interpulse intervals [interpulse interval (IPI): 20 to 30 msec), a lack of facilitation at intermediate IPIs (50 to 150 msec), and significantly less inhibition at longer IPIs (300 to 1,000 msec) than adults.
authors.affiliation: Biomedical Engineering Program, Trinity College/The University of Connecticut, Hartford, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Bronzino
authors.forename: J H
authors.initials: JH
authors.lastname: Blaise
authors.forename: P J
authors.initials: PJ
authors.lastname: Morgane
mesh_terms: D000367:Age Factors; D000818:Animals; D001698:Biomedical Engineering; D018891:Dentate Gyrus / Q000166:cytology* / Q000254:growth & development / Q000502:physiology*; D004558:Electric Stimulation; D004594:Electrophysiology; D005071:Evoked Potentials; D005246:Feedback; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley