The Effect of Prostaglandin E1 on Apotosis in Ischemic Skin Island Flap of Rats

Bae, Tae Hui; Lee, Ik Jun; Kim, Seung Han; Kim, Han Koo; Kim, Seung Hong; Lee, Tae Jin

Abstract

Apoptosis is a physiologic or programmed cell death process which is controlled by genes and it is essential for the function and the appropriate development of multicellular organism. Apoptosis is also thought to be one of the main mechanisms of cell death in ischemic tissues. The effect of prostaglandin E1(PGE1) is proven to be useful in the recovery of ischemic changes by inducing vasodilation of peripheral vessels and platelet disaggregation. Prostaglandin is also known to suppress apoptosis in a serum deprived cell. The purpose of this study is to evaluate the effects of PGE1 on the apoptosis in the ischemic skin island flap. Thirty Sprague-Dawley rats were used. In control group(n=15), 3x5cm sized skin island flap based on the superficial epigastric vessel was elevated and its pedicle was occluded for 14 hours. After removing the vessel clamp, skin flap was reperfused for 5 hours and harvested. In experimental group(n=15), a ischemic skin island flap was also made as in the control group except the interarterial administration of the PGE1 right after elevation of the flap and after removing the clamp. H&E, TUNEL and immunohistochemical stains for p53 and bax proteins were performed. There were ischemic changes in gross and microscopic findings in both groups. Immunohistochemical staining for p53 protein shows many positive cells with nuclear staining in squamous epithelium of the control group, but sparse positive cells in the experimental group. Immunohistochemical stainings for bax protein shows many positive cells with cytoplasmic staining in squamous epithelium of the control group, but sparse positive cells in the experimental group. The apoptotic index was significantly lower in the experimental group(2.39+/-1.76(p=0.0001)) than in the control group(7.53+/-2.05). These data indicate that PGE1 suppresses the apoptosis in the ischemic skin island flap.