Experimental autotransplantation of full-thickness skin into the mouth in adult dogs: Histochemical and microangiographic observations

Abstract

Full thickness skin autografts into the mouths of adult dogs were studied histochemically. Alkaline phosphatase in normal skin epithelium was negative, but the buccal epithelium was strongly positive. There was intense acid phosphatase activity in the skin and buccal epithelia. Oxidative enzymes in the normal skin epithelium were generally low as compared with oral epithelium. Alkaline phosphatase in the epithelium of the grafts was slightly positive on the 1st to 2nd post-operative weeks and later, but the activity of the acid phosphatase in the graft did not show any remarkable alteration following transplantation. The activity of oxidative enzymes in the graft disappeared during the first to fourth post-operative days. After that, the oxidative enzymatic reactive zone spread from the peripheral connective tissue of the graft towards the superficial region. The oxidative enzymes seemed to reappear in the epithelium of the graft in the 7th post-operative day. The level of oxidative enzyme activity of the graft was the same as that of normal oral mucosa after the 5th post-operative week. Microangiography using radio-opaque medium showed no blood vessels in the graft on the 3rd post-operative day. On the 5th day, a few blood vessels invaded the graft. The subepithelial region of the graft was revascularized on the 7th post-operative day. There appeared to be a relationship between the rate of revascularization of the graft and activity of its oxidative enzymes.