[Abstract Title]. - Society for Neuroscience

following single, mechanically elicited action potentials. We also used an antibody against low
voltage activated Ca 2+ channels to map their distribution across the three regions. Our results
indicate that Ca 2+ channels are located in all three regions. Mechanical stimulation produces
action potentials in the sensory dendrites that propagate rapidly through the neurons, causing a
similar time course and amplitude of intracellular [Ca 2+ ] elevation in all three regions.
Disclosures: U. Hoeger, None; A.S. French , None; S. Meisner, None; P.H. Torkkeli, None.
Poster
271. Mechanoreceptors
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 271.3/HH22
Topic: D.09.a. Cellular and molecular mechanisms of transduction
Support: JSPS Grant 19791571
Title: Invovement of GDNF in the periodontal Ruffini endings during regeneration
Authors: M. OISHI 1 , F. HARADA 1 , *S. WAKISAKA 2 , T. MAEDA 1 ;
1 Niigata Univ. Grad. Sch. Med. & Dent. Sci., Niigata, Japan; 2 Dept Oral Anat & Dev Biol,
Osaka Univ. Grad Sch. Dent., Osaka, Japan
Abstract: The Ruffini ending, categorized in a low-threshold type II stretch mechanoreceptor in
the periodontal ligament, has a high potential for neuroplasticity. Even in adulthood, this
mechanoreceptor has been reported to express immunoreactions for TrkB and p75-NGFR, both
of which can bind BDNF and NT-4/5 to mediate neurotrophic effects. Recently, our research
group has revealed that the expression of glial cell line-derived neurotrophic factor (GDNF) in
the periodontal Ruffini endings, suggesting that multiple nurotrophins are involved in their
development, regeneration, survival and maintenance. However, little information is available
for the involvement of GDNF in the periodontal Ruffini endings during regeneration. The
present study was undertaken to examine the expression pattern of GDNF in the periodontal
Ruffini endings after nerve injury to inferior alveolar nerve (IAN) by Immunohistochemistry.
Furthermore, the semi-quantitative analysis was employed to clarify the changes in expression of
GDNF mRNA in trigeminal ganglia during regeneration. Wistar rats (8-week-old) received a
transaction of IAN. At postoperative day 1, 3, 7, 14 and 28, the animals were fixed with 4%
paraformaldehyde. Frozen sections of trigeminal ganglia and decalcified lower jaws including
incisors were prepared and processed for immunohistochemistry for GDNF. Changes in GDNF
mRNA in the trigeminal ganglia were assessed by real time PCR. In non-surgery group, GDNFimmunoreaction
was found in the terminal Schwann cells associated with the periodontal Ruffini