The Turnovering After Heat Injury And The Protective Role Of Heat Shock Protein 90 From Fibroblasts Of Man's Skin In Vitro

Objective Investigate the morphological character,some functional changes and the protection of hsp90 from the derm'^s fibroblast after heat injury in deep-partical thickness burns,thus to provide guidance for the healing mechanism of "Auto epidermis overlap denatured derm in deep-partical thickerness".Method Human dermal fibroblasts were cultured in vitro and were heated under water at 52℃for 30s as the experimental group,the 37℃30s as the normal group.We used MTT,the microscope,transmission electron microscope,flow cytometry,LDH Kit,Na⁺ -K⁺-ATP enzyme kit,high performance liquid chromatography(HPLC),Co I ELASA Kit,FGF2 ELASA Kit,RT-PCR,Immunohistochemistry and Western blot to detect fibroblasts.Results The survival ratio of fibroblasts was about 50% when cells were stimulated at 52℃for 30s(P＜0.05,compared with the normal group).Moreover,We had observed obviously morphological changes of fibroblasts after heat injury.The injuring cells might restore to the notmality after 7 days.The S-stage in cell cycle from the experimental group was more sensitive to heating than the normal group(P＜0.01),Apoptosis was much more than the normal group(P＜0.01),too.Lactic acid dehydrogenase(LDH)leaking of the cell membrane from the experimental group was much higher than that of the normal group(P＜0.05)and might restore to the normality after 3 days(P＞0.05)We also found Na+ -K⁺-ATP enzyme of the cell membrane and ATP of the chondrosome from the experimental group was obviously lower than the normal group(P＜0.05).Na⁺-K⁺-ATP enzyme could recover to the normality after 2 days(P＞0.05).FGF2 outside fibroblasts from the experimental group was the same as the normal group on the first day,7th day and 10th after heat injury (P＞0.05),But FGF₂ from the experimental group was lower than the normal group from the second day to 5th day(P＜0.05),On the other hand,they themselves kept the relative stabilization(P＞0.05).The transcription and secretion of Col I from the experimental group were similar to the normal group(P＞0.05).The expression of hsp90 from the experimental group was obviously stronger than the normal group after 24h by immunohistochemistry,whether in kytoplasm or in nucelus.By Western Blot,We still saw the expressional number of hsp90 from the experimental group began to greatly increase after 3h,peaked on 24h,retained for 96h and restored to the normality.Conclusion The morphology of fibroblasts after heat injury could be changed.The metabolism rate and some functions from the experimental group were lower than the normal group,they might restore to normality from 2 to 7 days.Abnormaly high expression of hsp90 due to heat injury was found from the experimental group. Hsp90 might protect fibroblasts from heat injury.