IMMUNOHISTOCHEMICAL LOCALIZATION OF TRANSFORMING GROWTH-FACTOR-ALPHA IN THE MAJOR SALIVARY-GLANDS OF MALE AND FEMALE RATS

The three major salivary glands of normal male and female Fischer 344 rats of different ages were examined for the localization of epidermal growth factor (EGF) and transforming growth factor alpha (TGFalpha) b y immunohistochemical staining. EGF was demonstrated only in the granu lated convoluted tubule (GCT) cells of the submandibular gland, the re sults confirming the previous reports, and most abundantly in adult ma les and pregnant females. TGFalpha stain was localized in all three gl ands and was found throughout the entire duct system, excluding acinar cells. The myoepithelial cells of the sublingual gland were also reac tive with the TGFalpha antibody. The specificity of the staining was c onfirmed by negative staining reaction with the absorbed antibody and by radio-immunoassay and Western blot methods. This is the first repor t describing the presence of TGFalpha in the rat salivary glands.