[Study of neovascularization disturbance in deep partial-thickness scald in rats with diabetes mellitus]

To study the relationship between the degree of neovascularization and non-healing wounds in scalded rats with diabetic mellitus.

Sixty Sprague-Dawley rats were randomly divided into control group (C, n = 30, with treatment of isotonic saline) and streptozocin (STZ)-induced diabetic group (D, n = 30, with treatment of STZ), and then they were inflicted with 20% TBSA deep partial thickness scald. Wound specimens were harvested immediately after scald and on 1, 3, 7, 10, 14, 21 post scald days (PSD) to observe histological changes, and wound healing rates were calculated. Degree of neovascularization in wound (labeled with blue microsphere) and the quantity of vascular endothelial cells (labeled with red CD31) were also measured by double-labeling immunofluorescence.

Compared with those in C group, Wound healing rate and histological value scores were lowered, and the degree of neovascularization was abated markedly at each time point. The degree of neovascularization in D group (12.00 +/- 1.40) was obviously lower than that in C group on 7 PSD (60.00 +/- 3.00, P <0.01). There was no obvious difference in the number of vascular endothelial cells in both groups, however, the majority of endothelial cells had not formed functional capillaries in D group.

Vascular endothelial cell can proliferate actively with poor blood supply in diabetic nonhealing with deep partial-thickness scald wounds, but it is still poor in blood supply due to lack of functional capillaries.