Immunolocalization of heat shock proteins 27 and 47 during repair of induced oral ulcers.

Heat shock proteins (Hsps) 27 and 47 are involved in the control of apoptosis, cell migration, and collagen synthesis. There is some understanding of the immunolocalization of these proteins during the repair process in skin and gastrointestinal mucosa, but their expressions in normal and injured oral mucosa are unknown. The aim of this study was to analyze the immunolocalization and intensity of these proteins in oral ulcers induced in rats and to compare these expression levels with those reported in skin and gastric mucosa. Ulcers were induced on the ventral surface of the tongues of rats. The rats were then euthanized at 0, 24, 48, 72, and 120 h. Hsp27 expression remained low in the first hours of repair, but was higher at 72 h, mainly in the migrating epithelium. Expression of Hsp47 was high at 48 h, mainly in fibroblasts, cells of the vascular wall, and basal keratinocytes of migrating epithelium. In the control group, expressions of these proteins were low, which indicates that these Hsps are constitutive proteins in oral mucosa. Expression levels were similar to those reported in the healing of skin lesions and gastric ulcer, suggesting a common mechanism of Hsp activation in the repair of these tissues.