Lectin histochemistry on the apocrine sweat glands of dog dorsal skin

The secretory segment of apocrine sweat glands of the dog dorsal skin was studied by means of both conventional carbohydrate histochemistry and lectin histochemistry. Conventional glycoconjugate histochemistry revealed mostly neutral glycoproteins and partly acidic non sulphated glycoproteins in the apical protrusions of the secretory cells as well as in the luminal secretions of the glands. The lectin histochemistry showed Con A binding sites in the whole cytoplasm of the secretory cells. The supra-nuclear granules (probably including also Golgi elements) were labelled by SNA, MAA, RCA120, Con A, and GSA I-B4 thus indicating the presence of sialylated or asialylated N-linked oligosaccharides. The luminal surface of secretory cells reacted with all the lectins employed except with SBA. The apocrine protrusions revealed a general decrease in the lectin staining intensity, and lacking of GSA I-B4, UEA-I, and LTA reactivity. The luminal homogeneous matrix labelled SNA, WGA, GSA II, and GSA I-B4