title: Mechanoreceptive afferents exhibit functionally-specific activity dependent changes in conduction velocity.
abstract: Impulse activity in axons generates aftereffects on membrane excitability that can alter the conduction velocity of subsequently conducted impulses. We used a computerized stimulus pattern (a 1 Hz stimulus period followed by a period of repeated short bursts at 200 Hz) to assess in vivo activity-dependent changes in conduction latency of functionally identified rat cutaneous afferents conducting in the A beta range. Several different parameters of activity dependence were measured: burst supernormality, the average increase in conduction latency following conditioning with a single preceding impulse during high frequency burst stimulation; burst subnormality, the average latency increase during each burst; depression, a long-term increase in latency caused by the high frequency stimulation. The data show that different mechanosensitive A beta afferents with overlapping resting conduction velocities exhibit activity-dependent changes in conduction latency that are characteristic of their particular functions.
authors.affiliation: Department of Anesthesia Research Laboratories, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: S S
authors.initials: SS
authors.lastname: Waikar
authors.forename: J G
authors.initials: JG
authors.lastname: Thalhammer
authors.forename: S A
authors.initials: SA
authors.lastname: Raymond
authors.forename: J H
authors.initials: JH
authors.lastname: Huang
authors.forename: D S
authors.initials: DS
authors.lastname: Chang
authors.forename: G R
authors.initials: GR
authors.lastname: Strichartz
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology; D004558:Electric Stimulation; D008465:Mechanoreceptors / Q000502:physiology*; D009431:Neural Conduction / Q000502:physiology*; D009475:Neurons, Afferent / Q000502:physiology*; D051381:Rats; D012584:Sciatic Nerve / Q000166:cytology / Q000502:physiology; D012867:Skin / Q000294:innervation