The histological changes of diabetic rats' skin and the effects on the percutaneous absorption of glucocorticoid / 药学学报

ABSTRACT

To examine the histological changes of diabetic rats' skin and the effects on the percutaneous absorption of hydrocortisone (HC, a glucocorticoid), male Wistar rats were randomly divided into five groups: control group, diabetes one-week group (W1), two-week group (W2), three-week group (W3), and four-week group (W4), while each group contained 6 rats. Diabetes mellitus (DM) rat model was prepared with the method of streptozocin (STZ, 40 mg x kg(-1)) intraperitoneal injection. Abdominal skin was cut to carry out an in-vitro penetration experiment on an improved Franz diffusion cells, and phosphate buffer (PBS, pH 7.4) was used as receptor solution. The solution was analyzed with HPLC, and then the penetrating rate can be calculated. Meanwhile, rats' abdominal skins of different DM periods were HE stained and made into tissue slices to find if any histological changes occurred. The penetrating rate of control, W1, W2, W3, and W4 groups were 2.39 +/- 1.25, 3.22 +/- 1.72, 3.02 +/- 1.89, 3.63 +/- 2.02 and 5.00 +/- 3.36 microg x h(-1) x cm(-2), respectively. There was significant difference between the control and the W4 group (P < 0.05), but no significant differences were found between any other two groups (P > 0.05). The tissue slices showed that compared to the normal rats' skin, little change was observed in one-week DM rats' skin, but the skin of one-month DM rats' skin was observed thinner, and it became much thinner than that of rats with two-month diabetes, especially the epidermis. After making a rat into diabetic, the rats' skin goes through a pathological change, and this change is closely interrelated with the increase of the permeation of HC. Therefore, it is necessary to adjust the dose while some drug was applied on the skin in case of diabetes mellitus.