rMAP与胶原蛋白对大鼠伤口修复的影响研究

During the period from D1 to D14, the cells in the normal control group were arranged neatly and tightly, with a complete and clear structure of the epidermis. The collagen fibers in the dermis were densely interwoven, the cytoplasm was uniformly stained red, and the structures of appendages such as hair follicles and sebaceous glands were intact. The subcutaneous fat layer and muscle layer were clearly visible, with fat cells and muscle fibers arranged neatly and densely, uniform in size, and with normal nuclear morphology. In contrast, during the period from D1 to D14, the epidermis in the model control group showed incomplete keratinization, varying degrees of necrosis, and loss of structure, with cell disintegration and fragmentation, and thickening. The collagen fibers in the dermis also exhibited varying degrees of necrosis and loss of structure, with pale cytoplasmic staining, nuclear shrinkage or disappearance, and inflammatory cell infiltration, primarily lymphocytes and neutrophils. There was also varying degrees of fibrous tissue proliferation and mild hemorrhage in some areas, with a small accumulation of red blood cells. The conditions on D1 and D3 were particularly severe, while the inflammatory cell infiltration on D7 and D14 was less pronounced compared to D1 and D3. On D1 and D3, both the rMAP group and the collagen protein group showed incomplete keratinization of the epidermis, necrosis of the epidermal layer, and formation of new epidermis in some areas. The dermis contained a large number of necrotic collagen fibers and inflammatory cell infiltration, primarily lymphocytes and neutrophils. Compared to the model group, the rMAP group and the collagen protein group showed gradual improvement in the repair of the epidermis and dermis and a reduction in inflammatory cell infiltration at the D7 and D14 time points, with better recovery than the model group. 3.2 Effects of rMAP on Cytokine Expression in Wound Tissue of Rats After 7 days of treatment, compared to the normal control group, the model control group had significantly higher concentrations of IFN-γ, IL-2, IL-6, and TNF-α (all P < 0.01). Compared to the model control group, the rMAP group and the collagen protein group had significantly lower concentrations of these inflammatory cytokines, with statistically significant differences (all P < 0.05). However, there were no statistically significant differences in the concentrations of these inflammatory cytokines between the rMAP group and the collagen protein group (all P > 0.05), as shown in Table 1.