Effects of transcutaneous topical injection of oxygen on vascular endothelial growth factor gene into the healing ligament in rats.
The effects of intermittent exposure to oxygen injection on an experimentally induced ligament tear were studied in the right hind limb of 17 male Sprague-Dawley rats. Two rats were used for monitoring the partial oxygen pressure (pO(2)) of subcutaneous tissue and 15 rats were divided into the following three groups of 5 after an experimentally induced ligament tear: Group A, control group; Group B, injection of 0.5 ml hyaluronan to the wound transcutaneously; Group C, injection of 0.5 ml hyaluronan mixed with haemoglobin and oxygen (n=5). At 7 days post-ligament injury, we compared the ligaments of the three treatment groups for gross appearance, histology and expression of vascular endothelial growth factor (VEGF) mRNA by RT-PCR. Our results indicate that the pO(2) was immediately elevated to 334.6 mmHg by topical oxygen injection and this method was effective in promoting vessel formation in comparison to the control group (p<0.01). However, the expression of VEGF mRNA in the topical oxygen injection group (Group C) was lower than that in control group (p<0.05). Our results suggest that oxygen is able to accelerate vessel formation in spite of its effect of decreasing VEGF mRNA. Our method of using topical injection proved to be useful in healing the ligament and the wound.
Ishii
Yoshimasa
Y
3D Tissue Engineering Group, National Institute of Advanced Industrial Science and Technology, Japan. y-ishii@cg7.so-net.ne.jp
Ushida
Takashi
T
Tateishi
Tetsuya
T
Miyanaga
Yutaka
Y
D000279:Administration, Cutaneous; D000818:Animals; D004195:Disease Models, Animal; D015870:Gene Expression / Q000187:drug effects*; D006614:Hindlimb; D008297:Male; D010100:Oxygen / Q000008:administration & dosage* / Q000032:analysis; D017847:Patellar Ligament / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*; D014945:Wound Healing / Q000187:drug effects* / Q000502:physiology
D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; D010100:Oxygen