The Effects Of Connective Tissue Growth Factor On Survival Of The Random Skin Flap In Rats

OBJECTIVE: To investigate the effects of connective tissue growth factor(CTGF) on survival of the random skin flap in rats. METHOD: Thirty-two SD rats were randomized equally into 4 groups: CTGF120ng, CTGF160ng, CTGF200ng and control groups. Ischemic random dorsal skin flaps ( 2 cm x 8 cm) were constructed from the rats.In CTGF groups, Connective tissue growth factor (CTGF) was injected subcutaneously in skin flaps at the time of surgery .The same volume of 0.9% NaCl solution was injected in control group. Ten days later, the amount of viable tissue within the flap was measured by planimetry. After the animals were killed, and specimens from the random skin flaps were harvested for immunohistological and HE staining to examine the microvascular growth. RESULTS: The results of tissue survival planimetry of the skin flap of CTGF120ng, CTGF160ng, CTGF200ng and control groups were 10.1408±0.4348 cm2, 10.3871+0.5005 cm2 , 11.9938 ±0.6595 cm2 and 8.0566 ±1.0856 cm2, which were higher in the three CTGF group (P<0.05).And subcutaneous injection of CTGF at the dose of 200ng increased skin flap viability by about 25% compared with control group(P < 0.05). Immunohistochemical staining and HE staining revealed higher average vessel number as compared with the three CTGF groups and control group (the vessel number in the close part of each group is respectively 21.00 + 3.423, 27.38 + 3.114, 37.38 + 3.583, 13.88 ± 1.959,P<0.05).The number in the middle part of each group is 15.50+2.777, 24.63 + 3.335,28.63 ± 4.984 and 9.50 + 1.927, respectively (p<0.05). CONCLUSION: CTGF may enhance the survival of skin flaps in a dose-dependent manner, which is associated with an increase in angiogenesis of skin flaps .