Lingual lipase: immunocytochemical localization in the rat von Ebner gland

Rat lingual lipase was purified to homogeneity by solubilization in 1% octylglucoside, followed by centrifugation, affinity chromatography on hydroxylapatite, gel filtration, and chromatofocusing. Polyclonal antibodies to the enzyme were raised in rabbits, and monospecificity was established by immunoblotting. Tissues were embedded in either paraffin or Epon for light and transmission electron microscopy, respectively. Immunocytochemical localization of the enzyme was established using the peroxidase-antiperoxidase and streptavidin-gold techniques. Immunospecific staining was observed in all acinar cells of the serous von Ebner glands, but only in the demilunes of the lingual mucous glands. The secretory granules of the acinar cells of the von Ebner glands were stained with antilipase on electron microscopic examination. No staining was observed in the salivary glands, pancreas, esophagus, stomach, or duodenum. If a true gastric lipase exists in the rat, it is immunogenically distinct from lingual lipase.