[Experimental study on aqueous areca nut extracts inducing oral submucous fibrosis in rats. II. Effection of mast cells on collagen metabolism].

The effection of mast cells (MC) on collagen metabolism of oral submucous fibrosis (OSF) induced by aqueous areca nut extracts (AANE) in rats was studied by transmission electron microscope, histochemical and biochemical analyses. The results revealed that there was a close relationship between MC and fibroblats (FB) in the pathogensis of OSF; MC which appeared in the buccal mucosa in the model groups increased significantly and became more active in the function. A great deal of collagen compacted in the buccal mucosa in the model groups. The contents of tissue hydroxyproline (Hyp) in the model groups were obviously higher than those in the control groups. Moreover, the longer the time of irritation continued, the higher the contents were. The number of MC had a higher positive correlation with the contents of tissue Hyp at the same time. Total serum Hyp had no significant difference among all the groups and any stages. The results indicated that some aqueous components of areca nuts might disturb collagen metabolism by accumulation and activation of MC.