| Objective: A deep wounded model were made to examine the effects and mechanisms of disodium cromoglycate impacted on mast cell.Through observation of scar formation and quantity of mast cell as well as tryptase,hopefully we can confirm that mast cell play a vital role during wound healing process,and it is a potential target to prevent and treat pathologic scar.Methods: 40 SD rats were randomly selected,and each was disposed with two symmetrically deep grade wound about the size of 15 mm * 10 mm * 2mm on the back after shaved.Wounds were treated in exposure.All subjects were randomly and averagely assigned to four groups marked as A,B,C and D.Group A was treated with a dose of 40mg/kg disodium cromoglycate,while group B received 20mg/kg of it and group C received10mg/kg.Group D was a negative control group.Corresponding dose of disodium cromoglycate were intraperitoneal injected 30 min before the operation and 24 hours;48 hours;72hours postoperative.Same dose of water were injected among rats in group D.The wound width were measured regularly postoperative,and 3rd days wound tissue of left side were performed immuno-histochemical staining(Tryptase),HE staining and Toluidine blue staining.Wound healing time and final scar tissue width were recorded,and mean value was calculated for later comparison.Quantity of mast cell: Image-pro6.0 image analysis software system,Each immunohistochemical staining observed at high magnification for 5 horizons.Every value of a field of view of each specimen were measured,taking the mean of five vision asmean value of the specimen and compared.Tryptase analysis methods: Image-pro6.0image analysis software system.Each immunohistochemical staining observed at high magnification for 5 horizons.Every value of a field of view of each specimen were measured,taking the mean value of five vision as mean value of the specimen and compared.Results: 1.The initial area: Four pairwise comparisons P > 0.05,indicting that there was no significant difference among each group.2.Healing time: Four pairwise comparisons P > 0.05,indicting that there was no significant difference among each group.3.Scar width: in day 42,among the four groups,P<0.05,significant difference were showed in a sequence of A≈B<C<D.Scar tissue were softer in group A and B,while Group D showed firmness.4.Scar tissue in microscope: in day 42,four groups scar comparison,D group exhibited disorganized collagen fibers,locally swirling,while group A and B fibroblasts were tightly aligned in a nice order.Group C stayed between.5.Quantity of mast cell: According to the Toluidine blue staining results,the quantity of mast cell among four group shows no significant difference.Four groups pairwise comparison P<0.05,indicting that degranulated mast cell quantity vary among four groups in a scale of A≈B<C<D.6.Tryptase positive mast cell: In 3rd day,Four groups pairwise comparison P<0.05,indicting that tryptase positive mast cell quantity vary among four groups in a scale of A≈B > D > C.Conclusion: 1.Disodium cromoglycate impacted on the inflammation process by blocking mast cell from degranulating and mediator releasing,and less nascent capillaries as well as fibroblasts advented.the quantity of mast cell can not be influenced by using disodium cromoglycate,the healing timeand re-epithelialization show no sign of delaying.2.Scar formation were strongly induced using disodium cromoglycate during wound healing with a result of soft scar tissue and organized fibers.3.The function of mast cell were highly influenced when received a dose of 20mg/kg disodium cromoglycate,while less dose shows less influence.The impact were stable after reaching a peak value.4.Tryptase was important in the healing process by interacting with fibroblasts,and it shows a promising mechanisms of how mast cell influenced scar formation. |
