Biomedical subjects

I L Leknes

Publications and source records attributed to I L Leknes.

21 records · Page 2Linked to original sources

PubMed1981

Ultrastructure of myocardial widened Z bands and endocardial cells in two teleostean species.

Widened myocardial Z bands and endocardial cells are described in two teleostean species Cichlasoma meeki and Corydoras aeneus. Widened Z bands containing mainly amorphous and electron-dense material were seen in a number of myocardial cells. Further, similar material may occur in large amounts beneath the sarcolemma and at intercellular junctions. Occasionally, we observed continuity between the latter material and that in expanded Z bands. In C. meeki the ventricular endocardial layer consists of two structurally different cell types, whereas in C. aeneus only one cell type was seen. The functional aspects of widened Z bands are discussed.

Animals↗

PubMed1981

Ultrahistochemical studies on the moderately electron dense bodies in teleostean endocardial cells.

The staining properties of phosphotungstic acid (PTA) on moderately electron dense bodies (MDB), are studied in the endocardium of Gadus morrhua. In MDB fixed in aldehydes only, and stained with PTA at a low pH (0-1), Intensly electron dense material occurs on and beneath the limiting membrane. This latter area displays a declining electron density when stained with PTA solutions in which the pH is raised from 1 to 4. At pH greater than 5 the peripheral matrix appears nearly unstained. Collagen fibres fixed as above, and then stained with PTA at a low pH, appear electron dense. These results suggest that the peripheral matrix of the MDB consists mainly of basic proteins.

Animals↗

PubMed1980

Ultrastructure of atrial endocardium and myocardium in three species of gadidae (Teleostei).

The atrial endocardium and myocardium in three teleost species Gadiculus thori J. Smith, Melanogrammus aeglefinus (L.) and Onos cimbrius L. of the family Gadidae are described. The myocardial cells contain few myofibrils and a moderately developed sarcoplasmic reticulum and are connected by short nexuses. G. thori has many atrial specific granules in some of the myocardial cells facing the endocardium. Such cells contain little contractile material. The endocardium is composed of tall cells (10 micrometer) with basal extensions, protrusions of the surface and sometimes cytoplasmic bridges between adjacent cells. The endocardial cells contain bristle-coated vesicles, a well developed agranular endoplasmic reticulum, and many moderately dense bodies (MDB). MDB are membrane-bounded, contain tubules, granules and often fibres, and have different amounts of amorphous material and variable electron density. These bodies appear to fuse in a characteristic manner. Ultrahistochemical tests show that the granules in MDB probably contain catecholamines.

Animals↗