The effects of neuropeptides (calcitonin gene-related peptide and substance P) on cultured human pulp cells.
The sensory neuropeptides substance P and calcitonin gene-related peptide have been implicated in the mediation of pulpal inflammation. A possible role in healing following injury has also been suggested (Byers et al., 1990). This possibility has been investigated by an examination of a direct effect of substance P and calcitonin gene-related peptide in vitro on fibroblast-like cells derived from human dental pulp. Cells were cultured for 48 hr in Dulbecco's modified Eagle medium plus 20% fetal calf serum and antibiotics. Substance P and calcitonin gene-related peptide were added in the range from 10(-12) to 10(-4) mol/L. Fibroblast growth factor was used as a positive control. Effects on cell proliferation were assessed by cell counts (daily for 6 days) and [3H]-thymidine uptake (24 hr after the addition of peptides). An effect on cellular functional activity was measured by [35S]-sulfate incorporation into glycosaminoglycans, in confluent cell cultures. Both substance P and calcitonin gene-related peptide showed concentration-dependent stimulation of cell proliferation. The maximum stimulation of approximately 40% was achieved at substance P and calcitonin gene-related peptide concentrations of 10(-6) mol/L, comparable with stimulation by fibroblast growth factor. By contrast, little increase in glycosaminoglycan synthesis by confluent cells could be detected. The direct effect on pulp cells is consistent with a role of the neuropeptides in pulp healing. This is exerted at the level of cell proliferation, rather than functional activity.
Trantor
I R
IR
School of Dental Science, Faculty of Medicine, University of Melbourne, Australia.
Messer
H H
HH
Birner
R
R
D000293:Adolescent; D015740:Calcitonin Gene-Related Peptide / Q000502:physiology*; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D003782:Dental Pulp / Q000166:cytology / Q000187:drug effects / Q000294:innervation / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D006025:Glycosaminoglycans / Q000096:biosynthesis; D006801:Humans; D013268:Stimulation, Chemical; D013373:Substance P / Q000502:physiology*; D015854:Up-Regulation; D014945:Wound Healing / Q000502:physiology*
D006025:Glycosaminoglycans; D013373:Substance P; D004247:DNA; D015740:Calcitonin Gene-Related Peptide