Objective　To observe the histopathological features of early skin lesions and serum inflammatory mediators changes in the diabetes mellitus (DM) rats. 　Methods　A total of 50 Wistar rats at 8 to 10 weeks of age were divided into normal control group (C group

n=25) and diabetic group (DC group

n=25). The rats of DC group were given a high-glucose and high-fat diet for 2 weeks to induce insulin resistance and then an intraperitoneal injection of 35 mg/kg streptozotocin. All 25 rats were identified to be diabetic models with their fasting blood glucose over ≥7.0 mmol/L. Four rats of C group or DC group were killed to take the skin tissues in the 4th

8th and 12th weekend. In the 16th week

the heart blood samples of the left 13 rats of C group and 10 rats of DC group were collected to measure TNF-α

IL-6 and C-RP levels

and the skin samples were also taken for pathological observation and fullthickness and dermal thickness measurement. 　Results　In the 16th week

the TNF-α

IL-6 and C-RP levels of DC group were significantly higher than the normal group (P0.05). Micrometer measurements indicated that the skin full-thickness of diabetic rats became thinner and thinner in the 4th

8th

12th and 16th weeks

with significant difference when compared with normal group (P0.01

P0.05). The epidermal thickness of diabetic group were thinner compared with normal skin at all time points

but there was no statistical difference among them. Histological observations of the diabetic group showed that there were lesser clear epidermal cells

shrunk

swelling and degraded dermal layer of collagen

and progressive atrophy of subcutaneous fat. 　Conclusion　The successful established diabetic rat models show that their skin full-thickness and subcutaneous fat became thinner and atrophy

with significantly higher serum inflammatory cytokines.