A study on the distribution of several growth factors in the artificially created cleft lip wound healing of rabbit fetuses

Baek, Seung Hak; Yang, Won Sik

Abstract

Recently several growth factors such as TGF-beta1, TGF-beta2, PDGF, bFGF are known to play an important role in scar formation following adult tissue injury. But there is little known about the role of growth factors tissue healing without scar formation. Therefore the pupose of this study is to investigate the distribution of growth factors which are involved with scar formation in the artificially created lip wound healing of fetuses. The author had undergone hysterotomy and created cleft lip-like defects on fetuses of New Zealand White Rabbit in mid-third trimester (24 days). Fetuses were divided into 3 groups (the repired group, the unrepaired group and the sham-operated control group). At 1, 2, 3, 5, 7 days agter procedure, the repaired, the unrepaired and the control groups were obtained by Caeserean section. After documenting the viability of fetuses, fetuses were photographed to compare size and facial morphology and sectioned for histological examination by H & E stain and spatial and temporal deposition of TGF-beta1, TGF-beta2, PDGF, bFGF by immunohistochemical method. The findings are summarized as follows. 1. There were lack of inflammation and scar formation and nevascularity in the repaired and the unrepaired group during experimental periods. 2. The reepothelialization of the unrepaired group was slower than that of repaired group. 3. There wereon differences of distribution of bFGF in the control, the repaired and the unrenaired group. 4. PDGF was increased at post-op, first and second day and decreased agter post-op, third day. Eventully, there were no differences in the control, the repaired and the unrepaired group. 5. TGF-beta1 and TGF-beta2 were slightly increased at post-op, first and second day decreased after post-op, thied day. Eventually there were no differences in the control, the repaired and the unrepaired group. And TGF-beta2 is more densely stained than TGF-beta1.