title: Cerium-induced light-microscopic demonstration of 5'-nucleotidase activity in the lymphatic capillaries of the proximal oesophagus of the rat.
abstract: Lymphatic capillaries with narrow lumina cannot be identified with certainty by means of conventional light microscopy. This, however, can be achieved with great precision by means of labelling the 5'-nucleotidase activity which is high in lymphatic capillaries. In blood capillaries, on the other hand, it is either lacking or much less pronounced depending on the organ. The reactions performed thus far occurred primarily in the presence of lead ions which had a toxic effect on the enzymes. In cerium, however, this inhibiting influence can be neglected. 2 light-microscopic procedures of labelling the 5'-nucleotidase activity, which make use of cerium, are presented and compared here for the first time. The cerium perhydroxide technique is especially suited for demonstrating the lymphatic capillaries. In comparison to the previous enzyme histochemical methods, a definitely more precise demonstration of the endothelia of small lymphatics now is possible. The reason for this is that this method only reacts to regions of high enzyme activity. As opposed to previous tests on cryostat sections, the lumen of the lymphatic capillary is nearly always identifiable as such if employing this type of reaction. These properties of the cerium-perhydroxide reaction allow definite statements regarding the distribution of the lymphatic capillaries in the tissue. Its simple and rapid course of reaction favour the use of this method in clinical problems. In the other technique presented, the manganese dioxide technique, the demonstration of lymphatic capillaries is by far less exact due to its greater sensitivity even to low enzyme activities.
authors.affiliation: Department of Ear, Nose, and Throat Surgery, University of Kiel, FRG.
authors.forename: J A
authors.initials: JA
authors.lastname: Werner
authors.forename: M
authors.initials: M
authors.lastname: Schünke
mesh_terms: D015720:5'-Nucleotidase; D000818:Animals; D002563:Cerium; D004947:Esophagus / Q000201:enzymology*; D006651:Histocytochemistry; D008208:Lymphatic System / Q000166:cytology / Q000201:enzymology*; D008297:Male; D009708:Nucleotidases / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D002563:Cerium; D009708:Nucleotidases; D015720:5'-Nucleotidase