[The expression of platelet-derived growth factor-A and its receptor in acute radiation-induced skin ulcer in rats].
OBJECTIVE
To investigate the dynamic expression of platelet-derived growth factor-A (PDGF-A) and its receptor alpha (PDGFR-alpha) in different acute radiation-induced skin ulcers, and to explore the underlying mechanism involved in retarded healing of the ulcer.


METHODS
The model of acute radiation-induced skin ulcers in rats was replicated with 50 Gy 60Co gamma rays to the skin (radiation group, R, n = 55), rats with full - thickness skin excision wounds as control group (T, n = 55), and 5 normal rats to serve as normal control (NC) group. The expression of PDGF-A and PDGFR-alpha protein and PDGF-A mRNA was respectively assessed by means of histochemistry and in situ RT-PCR.


RESULTS
No PDGF-A expression was identified in the rat skin in NC group. The expression of PDGF-A and PDGFR were reduced in R group during inflammatory responsive and granulation formation periods (14 - 28 days after radiation, the IA value of PDGF-A varied from 14.0 +/- 1.2 to 20.3 +/- 1.2 compared with that in T group in which the IA value of PDGF-A at the same period (3 - 9 days after injury) varied from 20.0 +/- 1.6 to 28.3 +/- 1.0, and reduced gradually during scar formation period (55 days after radiation).


CONCLUSIONS
The reduction of PDGF-A and PDGFR-expression may be partially involved in the mechanism of retarded healing of acute radiation-induced skin ulcers.
Cao
Wei-hong
WH
Burn institute , First Affiliated Hospital , General Hospital of PLA (Formerly 304th Hospital ), Beijing 100037, P. R. China.
Chai
Jia-ke
JK
Yang
Zhi-xiang
ZX
Wang
De-wen
DW
Sheng
Zhi-yong
ZY
D000818:Animals; D005260:Female; D005720:Gamma Rays / Q000009:adverse effects; D010982:Platelet-Derived Growth Factor / Q000096:biosynthesis*; D011833:Radiation Injuries, Experimental / Q000150:complications / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000096:biosynthesis*; D012883:Skin Ulcer / Q000209:etiology / Q000378:metabolism*; D014945:Wound Healing
D010982:Platelet-Derived Growth Factor; C075278:platelet-derived growth factor A; D020796:Receptor, Platelet-Derived Growth Factor alpha