Abstract
Sensory nociceptive neurons not only have afferent functions but also peptidergic efferent functions which help to regulate immune and inflammatory responses by releasing neuro-peptides. Diabetes mellitus (DM) is well known to have peripheral neuropathy and the risk factor for periodontitis. The purpose of this study was to investigate the nerve fiber distribution and regeneration by using gingivectomy model of the experimental diabetic rats (DM rath). Three, 7, 14 days after gingivectomy, tissue were observed for nerve growth factor receptor (NGFR) and calcitonin gene-related peptide (CGRP) immunoreactivity. DM rats showed the decreasing NGFR immuno-reactive fibers in junctional epithelium compare to control. Reinnervation was also delayed with wound healing delay. DM group showed week CGRP immunorreactivity compare to control group. In the control group, 7 days after surgery, a number of increasing NGFR positive sprouting nerves were shown to have regenerative periodontal connective tissue compare to other time. These results indicate that the dye-back had already occured in gingival tissue, and delaied the sprouting and regeneration of nerve fibers. This reason speculates to decline of NGF expression include the wound healing delay. J. Jpn. Soc. Periodontol., 43: 155-165, 2001.
