List of abbreviations
Vocabulary
of micros-
copic
anatomy
specialist terms
explained in
English +
German

Every attempt was made to provide correct information and labelling, however any liability for eventual errors or incompleteness is rejected!

dieser Seite

Editor:
Dr. med.
H. Jastrow


Conditions
of use
Tendinocyte of a tendon of a human eye muscle
(for unlabelled original image click here, please!)

Af = Filamenta actinia (actin filaments = intracellular microfilaments); C = Cytoplasma (cytoplasm containing organells);
Clv = Vesiculum clathrinum (formation of a clathirn-coated vesicle is visible in the region of this Ed);
Dp = Diaphragma pori (membrane of a nuclear pore); Ec = Euchromatinum (euchromatin; merely electron-dense);
EF = Fibrilla elastica (elastic fibril consists of central El = Elastin [amorphous substance of elastic fibres] which is surrounded
by individual fibrillin Fi microfilaments); Ex = Exocytoses (exocytotic processes = transport of vesicles out of a cell);
Fi = Fibrillin (extracellular microfibrils of connective tissue); G = Apparatus golgiensis (Golgi-apparatus);
Kf = collagen fibrils (of type 1 and 3; note the different diameters of individual fibrils);
Ko = Fibrae collagenosae (collagen fibres in cross-section; consist of bestehend aus collagen fibrils which are interconnected
via proteoglycans Prg); Hc = Heterochromatinum (heterochromatin; electron-dense); Ly = Lysosomes;
Mam = Matrix mitochondrialis (mitochondrial matrix); Mi = Mitochondrion (mitochondrion of intermediate type);
Mm = Membranae mitochondriales (mitochondrialmembranes; the inner one has infoldings of variable widths into the Mam
further, there is an outer membrane); Mne = Membrana nuclearis externa (outer nuclear membrane);
Mni = Membrana nuclearis interna (inner nuclear membrane); N = Nucleus (nucleus);
P = Plasmalemma (cell membrane); Pc = Processus cellulares (immotile long thin processes of the tendinocyte
which contain Af and few organells); Pnu = Pori nucleares (pores of the nuclear membrane; covered with Dp);
Prg = proteoglykans (complexes of proteins with sugars which glue Kf to each other); R = single ribosomes;
RER = rough endoplasmic reticulum (intracellular network with bound ribosomes, continues into SER near to G);
SER = smooth endoplasmic reticulum (no ribosomes are attached here);
Sf = Substantia fundamentalis (amorphous ground substance, contains mainly water and therefore is not electron-dense);
Vs1 = Vesicula 1 (larger vesicles with merely electron-dense content); Vs2 = Vesicula 2 (very small vesicles).

The image shows a tendinocyte (Termonolgia histologica: Tendinocytus), the characteristic cell of a tendon. Tendinocytes are a kind of fibrocytes that shows very long thin immotile processes (Pc) that diverge in different directions between different collagen fibres (Ko). Tendinocytes rest in place and have a low metabolic activity which is demonstated by their poorness in cell organells. They synthetise the proteins which aggregate outside the cells to form collagenous and elastic fibrils. The latter are rarely seen in tendons. These secreted basic proteins are so small that they are not visible in the electron microscope, i.e. less than 0.5 nm in diameter). Further tendinocytes secrete proteoglycans (Prg) and other substances which form the amorphous ground substance (Substantia fundamentalis Sfa). Some of these are stored in vesicles Vs and transported to the cell membrane (P) and then released by exocytosis (Ex). Collagen fibres  (Ko) of tendons are oriented paralell to each other. Note that the diameters of the fibrils vary considerably in diameter depending on the amount of aggregated tropocollagen molecules of which they polymerise. They are formed by interconnected collagen fibrils (Kf) whereby proteoglycans (Prg) play a major role in connections. Since the shown preparation is a cross-section no longitudinally cut fibres are visible and thus the typical bands cannot be seen here.

--> tendon
--> elastic - collagenous fibres; ground substance; fibrocytes, connective tissue
--> Electron microscopic atlas Overview
--> Homepage of the workshop


Image, page & copyright H. Jastrow.